As filed with the Securities and Exchange Commission on May 9, 2019

Registration No. 333-

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Milestone Pharmaceuticals Inc.

(Exact name of registrant as specified in its charter)

Third Amended and Restated Stock Option Plan

2019 Equity Incentive Plan

2019 Employee Share Purchase Plan

(Full titles of the plans)

Joseph Oliveto

Chief Executive Officer

Milestone Pharmaceuticals USA Inc.

6000 Fairview Road, Suite 1200

Charlotte, NC 28210-2252

(514) 336-0444

(Name, address, including zip code and telephone number, including area code, of agent for service)

Copies to:

Ryan S. Sansom

Marc Recht

Jaime L. Chase

Cooley LLP

500 Boylston Street, 14th Floor

Boston, MA 02116

(617) 937-2300

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. x

CALCULATION OF REGISTRATION FEE

(1)          Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the “Securities Act”), this Registration Statement shall also cover any additional common shares that become issuable under the above-named plans by reason of any share dividend, share split, recapitalization or any other similar transaction effected without receipt of consideration which results in an increase in the number of Milestone Pharmaceuticals Inc.’s (the “Registrant”) outstanding common shares, no par value per share (the “Common Shares”).

(2)          Represents Common Shares reserved for issuance upon the exercise of outstanding options granted under the Registrant’s Third Amended and Restated Stock Option Plan, as amended (the “2011 Plan”). The 2011 Plan has been terminated and no further option grants will be made under the 2011 Plan, and any shares remaining available for future grants, plus any shares underlying outstanding options that terminate by expiration, forfeiture, cancellation or otherwise without the issuance of such shares, have been allocated to the Registrant’s 2019 Equity Incentive Plan (the “2019 Plan”).

(3)          Represents Common Shares reserved for future grant under the 2019 Plan. To the extent outstanding awards under the 2011 Plan terminate by expiration, forfeiture, cancellation or otherwise without the issuance of shares, the Common Shares subject to such awards instead will be available for future issuance under the 2019 Plan. The 2019 Plan also provides that an additional number of shares will automatically be added annually to the shares authorized for issuance under the 2019 Plan on January 1st of each year, for a period of not more than 10 years, commencing on January 1, 2020 and ending on (and including) January 1, 2029, in an amount equal to the lesser of (a) 4% of the total number of Common Shares outstanding on December 31st of the preceding calendar year and (b) a number of Common Shares designated by action of the Registrant’s board of directors prior to the first day of any calendar year.

(4)          Represents Common Shares reserved for issuance upon the exercise of outstanding options granted under the 2019 Plan.

(5)          Represents Common Shares reserved for issuance under the Registrant’s 2019 Employee Share Purchase Plan (the “ESPP”). The ESPP provides that an additional number of shares will automatically be added annually to the shares authorized for issuance under the ESPP on January 1, from 2020 until January 1, 2029. The number of shares added each year will be equal to the lesser of: (a) 1% of the total number of shares of the Registrant’s share capital outstanding on December 31 of the preceding calendar year; (b) 487,837 Common Shares and (c) a number of Common Shares designated by action of the Registrant’s board of directors prior to the first day of any calendar year.

(6)          Estimated pursuant to Rule 457(h) solely for the purpose of calculating the registration fee. The proposed maximum offering price per share and proposed maximum aggregate offering price are calculated using a weighted-average exercise price for such shares.

(7)          Estimated pursuant to Rule 457(h) solely for the purpose of calculating the registration fee. The proposed maximum offering price per share and proposed maximum aggregate offering price are calculated using the initial public offering price per share of the Registrant’s Common Shares as set forth in the Registrant’s prospectus filed with the Securities and Exchange Commission on May 9, 2019 pursuant to Rule 424(b) under the Securities Act.

(8)          Estimated pursuant to Rule 457(h) solely for the purpose of calculating the registration fee. The proposed maximum offering price per share and proposed maximum aggregate offering price are calculated using the exercise price for such shares.

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

The information called for by Part I of Form S-8 is omitted from this Registration Statement in accordance with Rule 428 of the Securities Act and the instructions to Form S-8. In accordance with the rules and regulations of the Securities and Exchange Commission (the “Commission”) and the instructions to Form S-8, such documents are not being filed with the Commission either as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.                          Incorporation of Documents by Reference.

Milestone Pharmaceuticals Inc. (the “Registrant”) hereby incorporates by reference into this Registration Statement the following documents filed by it with the Commission:

(a)    the Registrant’s prospectus filed on May 9, 2019 pursuant to Rule 424(b), dated May 8, 2019, under the Securities Act relating to the Registration Statement on Form S-1, as amended (File No. 333-230846), which contains audited financial statements for the Registrant’s latest fiscal year, for which such statements have been filed; and

(b)    the description of the Common Shares contained in the Registrant’s Registration Statement on Form 8-A (File No. 001-38899 filed with the Commission on May 6, 2019, under Section 12(b) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), including any amendments or reports filed for the purpose of updating such description.

All documents filed by the Registrant pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the filing of this Registration Statement and prior to the filing of a post-effective amendment which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference into this Registration Statement and to be a part hereof from the date of filing such documents, except as to specific sections of such documents as set forth therein. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement herein or in any subsequently

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filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not constitute a part of this Registration Statement, except as so modified or superseded.

Item 4.                          Description of Securities.

Not applicable.

Item 5.                          Interests of Named Experts and Counsel.

Not applicable.

Item 6.                          Indemnification of Directors and Officers.

In accordance with the provisions of the Business Corporations Act (Québec), the by-laws of the Registrant, to be adopted in connection with the closing, provide that the Registrant must indemnify a director or officer of the Registrant, a former director or officer of the Registrant, a mandatary, or any other person who acts or acted at the Registrant’s request as a director or officer of another group, (such director or officer, former director or officer, mandatary or person acting at the Registrant’s request is referred to as the “Indemnifiable Person” for the purposes of this Item 6) against all costs, charges and expenses reasonably incurred in the exercise of their functions, including an amount paid to settle an action or satisfy a judgment, or arising from any investigative or other proceeding in which the Indemnifiable Person is involved if: (i) the Indemnifiable Person acted with honesty and loyalty in the interest of the Registrant or, as the case may be, in the interest of the other group for which the Indemnifiable Person acted as director or officer or in a similar capacity at the Registrant’s request (“Condition A”); and (ii) in the case of a proceeding that is enforced by a monetary penalty, the Indemnifiable Person had reasonable grounds for believing that his or her conduct was lawful (“Condition B” and together with Condition A, the “Two Conditions”).

The Registrant must also advance moneys to an Indemnifiable Person for the costs, charges and expenses of a proceeding referred to in the preceding paragraph.

However, in the event that a court or any other competent authority judges that the Two Conditions are not fulfilled, or that the Indemnifiable Person has committed an intentional or gross fault, the Registrant may not indemnify the Indemnifiable Person and the Indemnifiable Person must repay to the Registrant any monies advanced.

In respect of an action by or on behalf of the Registrant or other group referred to above, against the Indemnifiable Person, the Registrant may, with the approval of the court, advance the necessary moneys to the Indemnifiable Person or indemnify the Indemnifiable Person against all costs, charges and expenses reasonably incurred by the Indemnifiable Person in connection with the action, if the Indemnifiable Person fulfills the Two Conditions.

The indemnity provided for in the preceding paragraphs can be obtained even if an Indemnifiable Person has ceased being a director, officer or representative of the Registrant. In case of death, the indemnity can be paid to the heirs, legatees, liquidators, assignees, authorized representants or beneficiaries of this Indemnifiable Person.

The Registrant must purchase and maintain insurance for the benefit of its directors, officers and other mandataries against any liability they may incur as such or in their capacity as directors, officers or mandataries of another group, if they act or acted in that capacity at the Registrant’s request.

The Registrant has entered into indemnification agreements with the Registrant’s directors and officers, whereby the Registrant has agreed to indemnify the Registrant’s directors and officers to the fullest extent permitted by law, including advancement of expenses incurred in legal proceedings to which the director or officer was, or is threatened to be made, a party by reason of the fact that such director or officer is or was a director, officer, employee or agent of the Registrant, provided that such director or officer acted in good faith and with a view to the best interest of the Registrant; and in the case of a criminal or administrative action or proceeding that is enforced by a monetary penalty, that such officer or director had reasonable grounds for believing their conduct was lawful. At present, there is no pending litigation or proceeding involving a director or officer of the Registrant regarding which indemnification is sought, nor is the Registrant aware of any threatened litigation that may result in claims for indemnification.

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The Registrant maintains insurance policies that indemnify the Registrant’s directors and officers against various liabilities arising under the Securities Act and the Exchange Act that might be incurred by any director or officer in his capacity as such.

Item 7.                          Exemption from Registration Claimed.

Not applicable.

Item 8.                          Exhibits.

The exhibits to this Registration Statement are listed below:

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Item 9.                          Undertakings.

A. The undersigned Registrant hereby undertakes:

1. To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the Registration Statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the Registration Statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective Registration Statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the Registration Statement or any material change to such information in the Registration Statement.

Provided, however, that paragraphs (A)(1)(i) and (A)(1)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the Registration Statement.

2. That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

3. To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

B. The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the Registration Statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

C. Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or

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controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Montréal, Province of Québec, Canada on May 9, 2019.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Joseph Oliveto and Timothy L. Maness, and each or any one of them, his or her true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them, or their or his or her substitutes or substitute, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement on Form S-8 has been signed by the following persons in the capacities and on the dates indicated.

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SIGNATURE OF AUTHORIZED U.S. REPRESENTATIVE OF THE REGISTRANT

Pursuant to the Securities Act, the undersigned, the duly authorized representative in the United States of Milestone Pharmaceuticals Inc. has signed this registration statement or amendment thereto on the 9th day of May, 2019.

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Exhibit 4.8

MILESTONE PHARMACEUTICALS INC.

2019 EQUITY INCENTIVE PLAN

ADOPTED BY THE BOARD OF DIRECTORS: APRIL 10, 2019

APPROVED BY THE SHAREHOLDERS: APRIL 29, 2019

IPO DATE: MAY 8, 2019

1.                                      GENERAL.

(a)                                 Successor to and Continuation of Prior Plan. The Plan is intended as the successor to and continuation of the Milestone Pharmaceuticals Inc. Third Amended and Restated Stock Option Plan (the “Prior Plan”). From and after 12:01 a.m. Eastern time on the IPO Date, no additional share awards will be granted under the Prior Plan. All Awards granted on or after 12:01 a.m. Eastern Time on the IPO Date will be granted under this Plan. All share awards granted under the Prior Plan will remain subject to the terms of the Prior Plan.

(i)                                    Any shares that would otherwise remain available for future grants under the Prior Plan as of 12:01 a.m. Eastern Time on the IPO Date (the “Prior Plan’s Available Reserve”) will cease to be available under the Prior Plan at such time. Instead, that number of Common Shares equal to the Prior Plan’s Available Reserve will be added to the Share Reserve (as further described in Section 3(a) below) and will be immediately available for grants and issuance pursuant to Share Awards hereunder, up to the maximum number set forth in Section 3(a) below.

(ii)                                In addition, from and after 12:01 a.m. Eastern time on the IPO Date, any shares subject, at such time, to outstanding share awards granted under the Prior Plan that (i) expire or terminate for any reason prior to exercise or settlement; (ii) are forfeited because of the failure to meet a contingency or condition required to vest such shares or otherwise return to the Company; or (iii) are reacquired, withheld (or not issued) to satisfy a tax withholding obligation in connection with an award or to satisfy the purchase price or exercise price of a share award (such shares the “Returning Shares”) will immediately be added to the Share Reserve (as further described in Section 3(a) below) as and when such shares become Returning Shares, up to the maximum number set forth in Section 3(a) below.

(b)                                 Eligible Award Recipients. Employees, Directors and Consultants are eligible to receive Awards.

(c)                                  Available Awards. The Plan provides for the grant of the following types of Awards: (i) Incentive Stock Options, (ii) Nonstatutory Stock Options, (iii) Share Appreciation Rights (iv) Restricted Share Awards, (v) Restricted Share Unit Awards, (vi) Performance Share Awards, (vii) Performance Cash Awards, and (viii) Other Share Awards.

(d)                                 Purpose. The Plan, through the granting of Awards, is intended to help the Company secure and retain the services of eligible award recipients, provide incentives for such persons to exert maximum efforts for the success of the Company and any Affiliate and provide a means by which the eligible recipients may benefit from increases in value of the Common Shares.

2.                                      ADMINISTRATION.

(a)                                 Administration by Board. The Board will administer the Plan. The Board may delegate administration of the Plan to a Committee or Committees, as provided in Section 2(c).

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(b)                                 Powers of Board. The Board will have the power, subject to, and within the limitations of, the express provisions of the Plan:

(i)                                    To determine (A) who will be granted Awards; (B) when and how each Award will be granted; (C) what type of Award will be granted; (D) the provisions of each Award (which need not be identical), including when a person will be permitted to exercise or otherwise receive cash or Common Shares under the Award; (E) the number of Common Shares subject to, or the cash value of, an Award; and (F) the Fair Market Value applicable to a Share Award.

(ii)                                To construe and interpret the Plan and Awards granted under it, and to establish, amend and revoke rules and regulations for administration of the Plan and Awards. The Board, in the exercise of these powers, may correct any defect, omission or inconsistency in the Plan or in any Award Agreement or in the written terms of a Performance Cash Award, in a manner and to the extent it will deem necessary or expedient to make the Plan or Award fully effective.

(iii)                            To settle all controversies regarding the Plan and Awards granted under it.

(iv)                             To accelerate, in whole or in part, the time at which an Award may be exercised or vest (or the time at which cash or Common Shares may be issued in settlement thereof).

(v)                                 To suspend or terminate the Plan at any time. Except as otherwise provided in the Plan or an Award Agreement, suspension or termination of the Plan will not materially impair a Participant’s rights under the Participant’s then-outstanding Award without the Participant’s written consent except as provided in subsection (viii) below.

(vi)                             To amend the Plan in any respect the Board deems necessary or advisable, including, without limitation, by adopting amendments relating to Incentive Stock Options and certain nonqualified deferred compensation under Section 409A of the Code and/or bringing the Plan or Awards granted under the Plan into compliance with the requirements for Incentive Stock Options or ensuring that they are exempt from or compliant with the requirements for nonqualified deferred compensation under Section 409A of the Code, subject to the limitations, if any, of applicable law. If required by applicable law or listing requirements, and except as provided in Section 9(a) relating to Capitalization Adjustments, the Company will seek shareholder approval of any amendment of the Plan that (A) materially increases the number of Common Shares available for issuance under the Plan, (B) materially expands the class of individuals eligible to receive Awards under the Plan, (C) materially increases the benefits accruing to Participants under the Plan, (D) materially reduces the price at which Common Shares may be issued or purchased under the Plan, (E) materially extends the term of the Plan, or (F) materially expands the types of Awards available for issuance under the Plan. Except as otherwise provided in the Plan or an Award Agreement, no amendment of the Plan will materially impair a Participant’s rights under an outstanding Award without the Participant’s written consent.

(vii)                         To submit any amendment to the Plan for shareholder approval, including, but not limited to, amendments to the Plan intended to satisfy the requirements of (A) Section 422 of the Code regarding incentive stock options or (B) Rule 16b-3.

(viii)                     To approve forms of Award Agreements for use under the Plan and to amend the terms of any one or more Awards, including, but not limited to, amendments to provide terms more favorable to the Participant than previously provided in the Award Agreement, subject to any specified limits in the Plan that are not subject to Board discretion; provided however, that a Participant’s rights under any Award will not be impaired by any such amendment unless (A) the Company requests the consent of the affected Participant, and (B) such Participant consents in writing. Notwithstanding the foregoing, (1) a

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Participant’s rights will not be deemed to have been impaired by any such amendment if the Board, in its sole discretion, determines that the amendment, taken as a whole, does not materially impair the Participant’s rights, and (2) subject to the limitations of applicable law, if any, the Board may amend the terms of any one or more Awards without the affected Participant’s consent (A) to maintain the qualified status of the Award as an Incentive Stock Option under Section 422 of the Code; (B) to change the terms of an Incentive Stock Option, if such change results in impairment of the Award solely because it impairs the qualified status of the Award as an Incentive Stock Option under Section 422 of the Code; (C) to clarify the manner of exemption from, or to bring the Award into compliance with, Section 409A of the Code; or (D) to comply with other applicable laws or listing requirements.

(ix)                             Generally, to exercise such powers and to perform such acts as the Board deems necessary or expedient to promote the best interests of the Company and that are not in conflict with the provisions of the Plan or Awards.

(x)                                 To adopt such procedures and sub-plans as are necessary or appropriate to permit participation in the Plan by Employees, Directors or Consultants who are foreign nationals or employed outside the United States (provided that Board approval will not be necessary for immaterial modifications to the Plan or any Award Agreement that are required for compliance with the laws of the relevant foreign jurisdiction).

(xi)                             To effect, with the consent of any adversely affected Participant, (A) the reduction of the exercise, purchase or strike price of any outstanding Share Award; (B) the cancellation of any outstanding Share Award and the grant in substitution therefor of a new (1) Option or SAR, (2) Restricted Share Award, (3) Restricted Share Unit Award, (4) Other Share Award, (5) cash and/or (6) other valuable consideration determined by the Board, in its sole discretion, with any such substituted award (x) covering the same or a different number of Common Shares as the cancelled Share Award and (y) granted under the Plan or another equity or compensatory plan of the Company; or (C) any other action that is treated as a repricing under generally accepted accounting principles.

(c)                                  Delegation to Committee.

(i)                                    General. The Board may delegate some or all of the administration of the Plan to a Committee or Committees. If administration of the Plan is delegated to a Committee, the Committee will have, in connection with the administration of the Plan, the powers theretofore possessed by the Board that have been delegated to the Committee, including the power to delegate to a subcommittee of the Committee any of the administrative powers the Committee is authorized to exercise (and references in this Plan to the Board will thereafter be to the Committee or subcommittee, as applicable). Any delegation of administrative powers will be reflected in resolutions, not inconsistent with the provisions of the Plan, adopted from time to time by the Board or Committee (as applicable). The Committee may, at any time, abolish the subcommittee and/or revest in the Committee any powers delegated to the subcommittee. The Board may retain the authority to concurrently administer the Plan with the Committee and may, at any time, revest in the Board some or all of the powers previously delegated.

(ii)                                Rule 16b-3 Compliance. The Committee may consist solely of two or more Non-Employee Directors, in accordance with Rule 16b-3.

(d)                                 Delegation to an Officer. The Board may delegate to one or more Officers the authority to do one or both of the following (i) designate Employees who are not Officers to be recipients of Options and SARs (and, to the extent permitted by applicable law, other Share Awards) and, to the extent permitted by applicable law, the terms of such Awards, and (ii) determine the number of Common Shares to be subject to such Share Awards granted to such Employees; provided, however, that the Board resolutions regarding

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such delegation will specify the total number of Common Shares that may be subject to the Share Awards granted by such Officer and that such Officer may not grant a Share Award to himself or herself. Any such Share Awards will be granted on the form of Share Award Agreement most recently approved for use by the Committee or the Board, unless otherwise provided in the resolutions approving the delegation authority. The Board may not delegate authority to an Officer who is acting solely in the capacity of an Officer (and not also as a Director) to determine the Fair Market Value pursuant to Section 13(w)(iii) below.

(e)                                  Effect of Board’s Decision. All determinations, interpretations and constructions made by the Board in good faith will not be subject to review by any person and will be final, binding and conclusive on all persons.

3.                                      SHARES SUBJECT TO THE PLAN.

(a)                                 Share Reserve. Subject to Section 9(a) relating to Capitalization Adjustments, and the following sentence regarding the annual increase, the aggregate number of shares of Common Stock that may be issued pursuant to Share Awards will not exceed 4,710,564 shares (the “Share Reserve”), which number is the sum of (i) 1,923,501 new shares, plus (ii) the number of shares subject to the Prior Plan’s Available Reserve plus (iii) the number of shares that are Returning Shares, as such shares become available from time to time. In addition, the Share Reserve will automatically increase on January 1st of each year, for a period of not more than ten years, commencing on January 1st of the year following the year in which the IPO Date occurs and ending on (and including) January 1, 2029, in an amount equal to 4% of the total number of shares of Capital Shares outstanding on December 31st of the preceding calendar year. Notwithstanding the foregoing, the Board may act prior to January 1st of a given year to provide that there will be no January 1st increase in the Share Reserve for such year or that the increase in the Share Reserve for such year will be a lesser number of Common Shares than would otherwise occur pursuant to the preceding sentence.

For clarity, the Share Reserve in this Section 3(a) is a limitation on the number of Common Shares that may be issued pursuant to the Plan. Accordingly, this Section 3(a) does not limit the granting of Share Awards except as provided in Section 7(a). Shares may be issued in connection with a merger or acquisition as permitted by NASDAQ Listing Rule 5635(c) or, if applicable, NYSE Listed Company Manual Section 303A.08, AMEX Company Guide Section 711 or other applicable rule, and such issuance will not reduce the number of shares available for issuance under the Plan.

(b)                                 Reversion of Shares to the Share Reserve. If a Share Award or any portion thereof (i) expires or otherwise terminates without all of the shares covered by such Share Award having been issued or (ii) is settled in cash (i.e., the Participant receives cash rather than shares), such expiration, termination or settlement will not reduce (or otherwise offset) the number of Common Shares that may be available for issuance under the Plan. If any Common Shares issued pursuant to a Share Award are forfeited back to or repurchased by the Company because of the failure to meet a contingency or condition required to vest such shares in the Participant, then the shares that are forfeited or repurchased will revert to and again become available for issuance under the Plan. Any shares subject to a Share Award (or portion thereof) that are surrendered to the Company in satisfaction of tax withholding obligations on a Share Award or as consideration for the exercise or purchase price of a Share Award will again become available for issuance under the Plan.

(c)                                  Incentive Stock Option Limit. Subject to the Share Reserve and Section 9(a) relating to Capitalization Adjustments, the aggregate maximum number of Common Shares that may be issued pursuant to the exercise of Incentive Stock Options will be 14,131,692 Common Shares.

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(d)                                 Limitation on Grants to Non-Employee Directors. The maximum number of shares of Common Stock subject to Share Awards granted under the Plan or otherwise during a single calendar year to any Non-Employee Director, taken together with any cash fees paid by the Company to such Non-Employee Director during such calendar year for service on the Board, will not exceed seven hundred fifty thousand dollars ($750,000) in total value (calculating the value of any such Share Awards based on the grant date fair value of such Share Awards for financial reporting purposes), or, with respect to the calendar year in which a Non-Employee Director is first appointed or elected to the Board,                  .

(e)                                  Source of Shares. The shares issuable under the Plan will be authorized but unissued Common Shares.

4.                                      ELIGIBILITY.

(a)                                 Eligibility for Specific Share Awards. Incentive Stock Options may be granted only to employees of the Company or a “parent corporation” or “subsidiary corporation” thereof (as such terms are defined in Sections 424(e) and 424(f) of the Code). Share Awards other than Incentive Stock Options may be granted to Employees, Directors and Consultants; provided, however, that Share Awards may not be granted to Employees, Directors and Consultants who are providing Continuous Service only to any “parent” of the Company, as such term is defined in Rule 405 of the Securities Act, unless (i) the shares underlying such Share Awards is treated as “service recipient stock” under Section 409A of the Code (for example, because the Share Awards are granted pursuant to a corporate transaction such as a spin off transaction), (ii) the Company, in consultation with its legal counsel, has determined that such Share Awards are otherwise exempt from Section 409A of the Code, or (iii) the Company, in consultation with its legal counsel, has determined that such Share Awards comply with the distribution requirements of Section 409A of the Code.

(b)                                 Ten Percent Shareholders. A Ten Percent Shareholder will not be granted an Incentive Stock Option unless the exercise price of such Option is at least 110% of the Fair Market Value on the date of grant and the Option is not exercisable after the expiration of five years from the date of grant.

5.                                      PROVISIONS RELATING TO OPTIONS AND SHARE APPRECIATION RIGHTS.

Each Option or SAR will be in such form and will contain such terms and conditions as the Board deems appropriate. All Options will be separately designated Incentive Stock Options or Nonstatutory Stock Options at the time of grant, and, if certificates are issued, a separate certificate or certificates will be issued for Common Shares purchased on exercise of each type of Option. If an Option is not specifically designated as an Incentive Stock Option, or if an Option is designated as an Incentive Stock Option but some portion or all of the Option fails to qualify as an Incentive Stock Option under the applicable rules, then the Option (or portion thereof) will be a Nonstatutory Stock Option. The provisions of separate Options or SARs need not be identical; provided, however, that each Award Agreement will conform to (through incorporation of provisions hereof by reference in the applicable Award Agreement or otherwise) the substance of each of the following provisions:

(a)                                 Term. Subject to the provisions of Section 4(b) regarding Ten Percent Shareholders, no Option or SAR will be exercisable after the expiration of ten (10) years from the date of its grant or such shorter period specified in the Award Agreement.

(b)                                 Exercise Price. Subject to the provisions of Section 4(b) regarding Ten Percent Shareholders, the exercise or strike price of each Option or SAR will be not less than 100% of the Fair Market Value of the Common Shares subject to the Option or SAR on the date the Award is granted. Notwithstanding the foregoing, an Option or SAR may be granted with an exercise or strike price lower

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than 100% of the Fair Market Value of the Common Shares subject to the Award if such Award is granted pursuant to an assumption of or substitution for another option or share appreciation right pursuant to a corporate transaction and in a manner consistent with the provisions of Section 409A of the Code and, if applicable, Section 424(a) of the Code. Each SAR will be denominated in Common Shares equivalents.

(c)                                  Purchase Price for Options. The purchase price of Common Shares acquired pursuant to the exercise of an Option may be paid, to the extent permitted by applicable law and as determined by the Board in its sole discretion, by any combination of the methods of payment set forth below. The Board will have the authority to grant Options that do not permit all of the following methods of payment (or otherwise restrict the ability to use certain methods) and to grant Options that require the consent of the Company to use a particular method of payment. The permitted methods of payment are as follows:

(i)                                    by cash, check, bank draft or money order payable to the Company;

(ii)                                pursuant to a program developed under Regulation T as promulgated by the Federal Reserve Board that, prior to the issuance of the shares subject to the Option, results in either the receipt of cash (or check) by the Company or the receipt of irrevocable instructions to pay the aggregate exercise price to the Company from the sales proceeds;

(iii)                            if an Option is a Nonstatutory Stock Option, by a “net exercise” arrangement pursuant to which the Company will reduce the number of Common Shares issuable upon exercise by the largest whole number of shares with a Fair Market Value that does not exceed the aggregate exercise price; provided, however, that the Company will accept a cash or other payment from the Participant to the extent of any remaining balance of the aggregate exercise price not satisfied by such reduction in the number of whole shares to be issued. Common Shares will no longer be subject to an Option and will not be exercisable thereafter to the extent that (A) shares otherwise issuable upon exercise are used to pay the exercise price pursuant to the “net exercise,” (B) shares are delivered to the Participant as a result of such exercise, and (C) shares otherwise issuable are withheld to satisfy tax withholding obligations; or

(iv)                             in any other form of legal consideration that may be acceptable to the Board and specified in the applicable Award Agreement.

(d)                                 Exercise and Payment of a SAR. To exercise any outstanding SAR, the Participant must provide written notice of exercise to the Company in compliance with the provisions of the Share Appreciation Right Agreement evidencing such SAR. The appreciation distribution payable on the exercise of a SAR will be not greater than an amount equal to the excess of (A) the aggregate Fair Market Value (on the date of the exercise of the SAR) of a number of Common Shares equal to the number of Common Share equivalents in which the Participant is vested under such SAR, and with respect to which the Participant is exercising the SAR on such date, over (B) the aggregate strike price of the number of Common Share equivalents with respect to which the Participant is exercising the SAR on such date. The appreciation distribution may be paid in Common Shares, in cash, in any combination of the two or in any other form of consideration, as determined by the Board and contained in the Award Agreement evidencing such SAR.

(e)                                  Transferability of Options and SARs. The Board may, in its sole discretion, impose such limitations on the transferability of Options and SARs as the Board will determine. In the absence of such a determination by the Board to the contrary, the following restrictions on the transferability of Options and SARs will apply:

(i)                                    Restrictions on Transfer. An Option or SAR will not be transferable except by will or by the laws of descent and distribution (or pursuant to subsections (ii) and (iii) below), and will be exercisable during the lifetime of the Participant only by the Participant. The Board may permit transfer of

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the Option or SAR in a manner that is not prohibited by applicable tax and securities laws. Except as explicitly provided herein, neither an Option nor a SAR may be transferred for consideration.

(ii)                                Domestic Relations Orders. Subject to the approval of the Board or a duly authorized Officer, an Option or SAR may be transferred pursuant to the terms of a domestic relations order, official marital settlement agreement or other divorce or separation instrument as permitted by Treasury Regulation Section 1.421-1(b)(2). If an Option is an Incentive Stock Option, such Option may be deemed to be a Nonstatutory Stock Option as a result of such transfer.

(iii)                            Beneficiary Designation. Subject to the approval of the Board or a duly authorized Officer, a Participant may, by delivering written notice to the Company, in a form approved by the Company (or the designated broker), designate a third party who, on the death of the Participant, will thereafter be entitled to exercise the Option or SAR and receive the Common Shares or other consideration resulting from such exercise. In the absence of such a designation, upon the death of the Participant, the executor or administrator of the Participant’s estate will be entitled to exercise the Option or SAR and receive the Common Shares or other consideration resulting from such exercise. However, the Company may prohibit designation of a beneficiary at any time, including due to any conclusion by the Company that such designation would be inconsistent with the provisions of applicable laws.

(f)                                   Vesting Generally. The total number of Common Shares subject to an Option or SAR may vest and become exercisable in periodic installments that may or may not be equal. The Option or SAR may be subject to such other terms and conditions on the time or times when it may or may not be exercised (which may be based on the satisfaction of Performance Goals or other criteria) as the Board may deem appropriate. The vesting provisions of individual Options or SARs may vary. The provisions of this Section 5(f) are subject to any Option or SAR provisions governing the minimum number of Common Shares as to which an Option or SAR may be exercised.

(g)                                 Termination of Continuous Service. Except as otherwise provided in the applicable Award Agreement or other agreement between the Participant and the Company, if a Participant’s Continuous Service terminates (other than for Cause and other than upon the Participant’s death or Disability), the Participant may exercise his or her Option or SAR (to the extent that the Participant was entitled to exercise such Award as of the date of termination of Continuous Service), but only within the period of time ending on the earlier of (i) the date that is three (3) months following the termination of the Participant’s Continuous Service (or such longer or shorter period specified in the applicable Award Agreement, which period will not be less than thirty (30) days if necessary to comply with applicable laws unless such termination is for Cause) and (ii) the expiration of the term of the Option or SAR as set forth in the Award Agreement. If, after termination of Continuous Service, the Participant does not exercise his or her Option or SAR within the applicable time frame, the Option or SAR as applicable will terminate.

(h)                                 Extension of Termination Date. Except as otherwise provided in the applicable Award Agreement or other written agreement between the Participant and the Company, if the exercise of an Option or SAR following the termination of the Participant’s Continuous Service (other than for Cause and other than upon the Participant’s death or Disability) would be prohibited at any time solely because the issuance of Common Shares would violate the registration requirements under the Securities Act, then the Option or SAR will terminate on the earlier of (i) the expiration of a total period of time (that need not be consecutive) equal to the applicable post termination exercise period after the termination of the Participant’s Continuous Service during which the exercise of the Option or SAR would not be in violation of such registration requirements or other applicable securities laws, and (ii) the expiration of the term of the Option or SAR as set forth in the applicable Award Agreement. In addition, unless otherwise provided in a Participant’s Award Agreement, if the sale of any Common Shares received on exercise of an Option or SAR following the termination of the Participant’s Continuous Service (other than for Cause) would

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violate the Company’s insider trading policy, then the Option or SAR will terminate on the earlier of (i) the expiration of a period of months (that need not be consecutive) equal to the applicable post-termination exercise period after the termination of the Participant’s Continuous Service during which the sale of the Common Shares received upon exercise of the Option or SAR would not be in violation of the Company’s insider trading policy, or (ii) the expiration of the term of the Option or SAR as set forth in the applicable Award Agreement.

(i)                                    Disability of Participant. Except as otherwise provided in the applicable Award Agreement or other agreement between the Participant and the Company, if a Participant’s Continuous Service terminates as a result of the Participant’s Disability, the Participant may exercise his or her Option or SAR (to the extent that the Participant was entitled to exercise such Option or SAR as of the date of termination of Continuous Service), but only within such period of time ending on the earlier of (i) the date twelve (12) months following such termination of Continuous Service (or such longer or shorter period specified in the Award Agreement, which period will not be less than six (6) months if necessary to comply with applicable laws) and (ii) the expiration of the term of the Option or SAR as set forth in the Award Agreement. If, after termination of Continuous Service, the Participant does not exercise his or her Option or SAR within the applicable time frame, the Option or SAR (as applicable) will terminate.

(j)                                    Death of Participant. Except as otherwise provided in the applicable Award Agreement or other agreement between the Participant and the Company, if (i) a Participant’s Continuous Service terminates as a result of the Participant’s death, or (ii) the Participant dies within the period (if any) specified in the Award Agreement for exercisability after the termination of the Participant’s Continuous Service for a reason other than death, then the Option or SAR may be exercised (to the extent the Participant was entitled to exercise such Option or SAR as of the date of death) by the Participant’s estate, by a person who acquired the right to exercise the Option or SAR by bequest or inheritance or by a person designated to exercise the Option or SAR upon the Participant’s death, but only within the period ending on the earlier of (i) the date eighteen (18) months following the date of death (or such longer or shorter period specified in the Award Agreement, which period will not be less than six (6) months if necessary to comply with applicable laws) and (ii) the expiration of the term of such Option or SAR as set forth in the Award Agreement. If, after the Participant’s death, the Option or SAR is not exercised within the applicable time frame, the Option or SAR (as applicable) will terminate.

(k)                                 Termination for Cause. Except as explicitly provided otherwise in a Participant’s Award Agreement or other individual written agreement between the Company or any Affiliate and the Participant, if a Participant’s Continuous Service is terminated for Cause, the Option or SAR will terminate immediately upon such Participant’s termination of Continuous Service, and the Participant will be prohibited from exercising his or her Option or SAR from and after the time of such termination of Continuous Service.

(l)                                    Non-Exempt Employees. If an Option or SAR is granted to an Employee who is a non-exempt employee for purposes of the Fair Labor Standards Act of 1938, as amended, the Option or SAR will not be first exercisable for any Common Shares until at least six (6) months following the date of grant of the Option or SAR (although the Award may vest prior to such date). Consistent with the provisions of the Worker Economic Opportunity Act, (i) if such non-exempt Employee dies or suffers a Disability, (ii) upon a Corporate Transaction in which such Option or SAR is not assumed, continued, or substituted, (iii) upon a Change in Control, or (iv) upon the Participant’s retirement (as such term may be defined in the Participant’s Award Agreement, in another agreement between the Participant and the Company, or, if no such definition, in accordance with the Company’s then current employment policies and guidelines), the vested portion of any Options and SARs may be exercised earlier than six (6) months following the date of grant. The foregoing provision is intended to operate so that any income derived by a non-exempt employee in connection with the exercise or vesting of an Option or SAR will be exempt from his or her regular rate of pay. To the extent permitted and/or required for compliance with the Worker Economic Opportunity Act

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to ensure that any income derived by a non-exempt employee in connection with the exercise, vesting or issuance of any shares under any other Share Award will be exempt from the employee’s regular rate of pay, the provisions of this Section 5(l) will apply to all Share Awards and are hereby incorporated by reference into such Share Award Agreements.

6.                                      PROVISIONS OF SHARE AWARDS OTHER THAN OPTIONS AND SARS.

(a)                                 Restricted Share Awards. Each Restricted Share Award Agreement will be in such form and will contain such terms and conditions as the Board deems appropriate. To the extent consistent with the Company’s bylaws, at the Board’s election, Common Shares may be (i) held in book entry form subject to the Company’s instructions until any restrictions relating to the Restricted Share Award lapse; or (ii) evidenced by a certificate, which certificate will be held in such form and manner as determined by the Board. The terms and conditions of Restricted Share Award Agreements may change from time to time, and the terms and conditions of separate Restricted Share Award Agreements need not be identical. Each Restricted Share Award Agreement will conform to (through incorporation of the provisions hereof by reference in the agreement or otherwise) the substance of each of the following provisions:

(i)                                    Consideration. A Restricted Share Award may be awarded in consideration for (A) cash, check, bank draft or money order payable to the Company, (B) past services to the Company or an Affiliate, or (C) any other form of legal consideration that may be acceptable to the Board, in its sole discretion, and permissible under applicable law.

(ii)                                Vesting. Common Shares awarded under the Restricted Share Award Agreement may be subject to forfeiture to the Company in accordance with a vesting schedule to be determined by the Board.

(iii)                            Termination of Participant’s Continuous Service. If a Participant’s Continuous Service terminates, the Company may receive through a forfeiture condition or a repurchase right any or all of the Common Shares held by the Participant as of the date of termination of Continuous Service under the terms of the Restricted Share Award Agreement.

(iv)                             Transferability. Common Shares acquired under the Restricted Share Award Agreement will be transferable by the Participant only upon such terms and conditions as are set forth in the Restricted Share Award Agreement, as the Board will determine in its sole discretion, so long as Common Shares awarded under the Restricted Share Award Agreement remains subject to the terms of the Restricted Share Award Agreement.

(v)                                 Dividends. A Restricted Share Award Agreement may provide that any dividends paid on Common Shares will be subject to the same vesting and forfeiture restrictions as apply to the shares subject to the Restricted Share Award to which they relate.

(b)                                 Restricted Share Unit Awards. Each Restricted Share Unit Award Agreement will be in such form and will contain such terms and conditions as the Board deems appropriate. The terms and conditions of Restricted Share Unit Award Agreements may change from time to time, and the terms and conditions of separate Restricted Share Unit Award Agreements need not be identical. Each Restricted Share Unit Award Agreement will conform to (through incorporation of the provisions hereof by reference in the agreement or otherwise) the substance of each of the following provisions:

(i)                                    Consideration. At the time of grant of a Restricted Share Unit Award, the Board will determine the consideration, if any, to be paid by the Participant upon delivery of each Common Share subject to the Restricted Share Unit Award. The consideration to be paid (if any) by the Participant for each

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Common Share subject to a Restricted Share Unit Award may be paid in any form of legal consideration that may be acceptable to the Board, in its sole discretion, and permissible under applicable law.

(ii)                                Vesting. At the time of the grant of a Restricted Share Unit Award, the Board may impose such restrictions on or conditions to the vesting of the Restricted Share Unit Award as it, in its sole discretion, deems appropriate.

(iii)                            Payment. A Restricted Share Unit Award may be settled by the delivery of Common Shares, their cash equivalent, any combination thereof or in any other form of consideration, as determined by the Board and contained in the Restricted Share Unit Award Agreement.

(iv)                             Additional Restrictions. At the time of the grant of a Restricted Share Unit Award, the Board, as it deems appropriate, may impose such restrictions or conditions that delay the delivery of the Common Shares (or their cash equivalent) subject to a Restricted Share Unit Award to a time after the vesting of such Restricted Share Unit Award.

(v)                                 Dividend Equivalents. Dividend equivalents may be credited in respect of Common Shares covered by a Restricted Share Unit Award, as determined by the Board and contained in the Restricted Share Unit Award Agreement. At the sole discretion of the Board, such dividend equivalents may be converted into additional Common Shares covered by the Restricted Share Unit Award in such manner as determined by the Board. Any additional shares covered by the Restricted Share Unit Award credited by reason of such dividend equivalents will be subject to all of the same terms and conditions of the underlying Restricted Share Unit Award Agreement to which they relate.

(vi)                             Termination of Participant’s Continuous Service. Except as otherwise provided in the applicable Restricted Share Unit Award Agreement or other written agreement between a Participant and the Company or an Affiliate, such portion of the Restricted Share Unit Award that has not vested will be forfeited upon the Participant’s termination of Continuous Service.

(c)                                  Performance Awards.

(i)                                    Performance Share Awards. A Performance Share Award is a Share Award that is payable (including that may be granted, may vest or may be settled) contingent upon the attainment during a Performance Period of certain Performance Goals. A Performance Share Award may, but need not, require the Participant’s completion of a specified period of Continuous Service. The length of any Performance Period, the Performance Goals to be achieved during the Performance Period, and the measure of whether and to what degree such Performance Goals have been attained will be conclusively determined by the Board or Committee, in its sole discretion. In addition, to the extent permitted by applicable law and the applicable Award Agreement, the Board or the Committee may determine that cash may be used in payment of Performance Share Awards.

(ii)                                Performance Cash Awards. A Performance Cash Award is a cash award that is payable contingent upon the attainment during a Performance Period of certain Performance Goals. A Performance Cash Award may also require the completion of a specified period of Continuous Service. At the time of grant of a Performance Cash Award, the length of any Performance Period, the Performance Goals to be achieved during the Performance Period, and the measure of whether and to what degree such Performance Goals have been attained will be conclusively determined by the Board or Committee, in its sole discretion. The Board or Committee may specify the form of payment of Performance Cash Awards, which may be cash or other property, or may provide for a Participant to have the option for his or her Performance Cash Award, or such portion thereof as the Board may specify, to be paid in whole or in part in cash or other property.

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(iii)                            Board Discretion. The Board retains the discretion to adjust or eliminate the compensation or economic benefit due upon attainment of Performance Goals and to define the manner of calculating the Performance Criteria it selects to use for a Performance Period. Partial achievement of the specified criteria may result in the payment or vesting corresponding to the degree of achievement as specified in the Share Award Agreement or the written terms of a Performance Cash Award.

(d)                                 Other Share Awards. Other forms of Share Awards valued in whole or in part by reference to, or otherwise based on, Common Shares, including the appreciation in value thereof (e.g., options or share rights with an exercise price or strike price less than 100% of the Fair Market Value of the Common Shares at the time of grant) may be granted either alone or in addition to Share Awards provided for under Section 5 and the preceding provisions of this Section 6. Subject to the provisions of the Plan, the Board will have sole and complete authority to determine the persons to whom and the time or times at which such Other Share Awards will be granted, the number of Common Shares (or the cash equivalent thereof) to be granted pursuant to such Other Share Awards and all other terms and conditions of such Other Share Awards.

7.                                      COVENANTS OF THE COMPANY.

(a)                                 Availability of Shares.  The Company will keep available at all times the number of Common Shares reasonably required to satisfy then outstanding Share Awards.

(b)                                 Securities Law Compliance. The Company will seek to obtain from each regulatory commission or agency having jurisdiction over the Plan, as necessary, such authority as may be required to grant Share Awards and to issue Common Shares upon exercise or settlement of the Share Awards; provided, however, that this undertaking will not require the Company to register under the Securities Act or other securities or applicable laws, the Plan, any Share Award or any Common Shares issued or issuable pursuant to any such Share Award. If, after reasonable efforts and at a reasonable cost, the Company is unable to obtain from any such regulatory commission or agency the authority that counsel for the Company deems necessary or advisable for the lawful issuance of Common Shares under the Plan, the Company will be relieved from any liability for failure to issue Common Shares upon exercise or settlement of such Share Awards unless and until such authority is obtained. A Participant will not be eligible for the grant of an Award or the subsequent issuance of cash or Common Shares pursuant to the Award if such grant or issuance would be in violation of any applicable securities law.

(c)                                  No Obligation to Notify or Minimize Taxes. The Company will have no duty or obligation to any Participant to advise such holder as to the tax treatment or time or manner of exercising such Share Award. Furthermore, the Company will have no duty or obligation to warn or otherwise advise such holder of a pending termination or expiration of an Award or a possible period in which the Award may not be exercised. The Company has no duty or obligation to minimize the tax consequences of an Award to the holder of such Award.

8.                                      MISCELLANEOUS.

(a)                                 Use of Proceeds from Issuance of Common Shares. Proceeds from the issuance of Common Shares pursuant to Share Awards will constitute general funds of the Company.

(b)                                 Corporate Action Constituting Grant of Awards. Corporate action constituting a grant by the Company of an Award to any Participant will be deemed completed as of the date of such corporate action, unless otherwise determined by the Board, regardless of when the instrument, certificate, or letter evidencing the Award is communicated to, or actually received or accepted by, the Participant. In the event that the corporate records (e.g., Board consents, resolutions or minutes) documenting the corporate action

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approving the grant contain terms (e.g., exercise price, vesting schedule or number of shares) that are inconsistent with those in the Award Agreement or related grant documents as a result of a clerical error in the papering of the Award Agreement or related grant documents, the corporate records will control and the Participant will have no legally binding right to the incorrect term in the Award Agreement or related grant documents.

(c)                                  Shareholder Rights. No Participant will be deemed to be the holder of, or to have any of the rights of a holder with respect to, any Common Shares subject to an Award unless and until (i) such Participant has satisfied all requirements for exercise of, or the issuance of Common Shares under, the Award pursuant to its terms, and (ii) the issuance of the Common Shares subject to such Award has been entered into the books and records of the Company.

(d)                                 No Employment or Other Service Rights. Nothing in the Plan, any Award Agreement or any other instrument executed thereunder or in connection with any Award granted pursuant thereto will confer upon any Participant any right to continue to serve the Company or an Affiliate in the capacity in effect at the time the Award was granted or will affect the right of the Company or an Affiliate to terminate (i) subject to applicable employment standards legislation, the employment of an Employee with or without notice and with or without cause, (ii) the service of a Consultant pursuant to the terms of such Consultant’s agreement with the Company or an Affiliate, or (iii) the service of a Director pursuant to the bylaws of the Company or an Affiliate, and any applicable provisions of the corporate law of the state or foreign jurisdiction in which the Company or the Affiliate is domiciled or incorporated, as the case may be.

(e)                                  Change in Time Commitment. In the event a Participant’s regular level of time commitment in the performance of his or her services for the Company and any Affiliates is reduced (for example, and without limitation, if the Participant is an Employee of the Company and the Employee has a change in status from a full-time Employee to a part-time Employee or takes a leave of absence) after the date of grant of any Award to the Participant, subject to applicable employment standards legislation, the Board has the right in its sole discretion to (x) make a corresponding reduction in the number of shares or cash amount subject to any portion of such Award that is scheduled to vest or become payable after the date of such change in time commitment, and (y) in lieu of or in combination with such a reduction, extend the vesting or payment schedule applicable to such Award. In the event of any such reduction, the Participant will have no right with respect to any portion of the Award that is so reduced or extended.

(f)                                   Incentive Stock Option Limitations. To the extent that the aggregate Fair Market Value (determined at the time of grant) of Common Shares with respect to which Incentive Stock Options are exercisable for the first time by any Optionholder during any calendar year (under all plans of the Company and any Affiliates) exceeds $100,000 (or such other limit established in the Code) or otherwise does not comply with the rules governing Incentive Stock Options, the Options or portions thereof that exceed such limit (according to the order in which they were granted) or otherwise do not comply with such rules will be treated as Nonstatutory Stock Options, notwithstanding any contrary provision of the applicable Option Agreement(s).

(g)                                 Investment Assurances. The Company may require a Participant, as a condition of exercising or acquiring Common Shares under any Award, (i) to give written assurances satisfactory to the Company as to the Participant’s knowledge and experience in financial and business matters and/or to employ a purchaser representative reasonably satisfactory to the Company who is knowledgeable and experienced in financial and business matters and that such Participant is capable of evaluating, alone or together with the purchaser representative, the merits and risks of exercising the Award; and (ii) to give written assurances satisfactory to the Company stating that the Participant is acquiring Common Shares subject to the Award for the Participant’s own account and not with any present intention of selling or otherwise distributing the Common Shares. The foregoing requirements, and any assurances given pursuant

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to such requirements, will be inoperative if (A) the issuance of the shares upon the exercise or acquisition of Common Shares under the Share Award has been registered under a then currently effective registration statement under the Securities Act, or (B) as to any particular requirement, a determination is made by counsel for the Company that such requirement need not be met in the circumstances under the then applicable securities laws. The Company may, upon advice of counsel to the Company, place legends on share certificates issued under the Plan as such counsel deems necessary or appropriate in order to comply with applicable securities laws, including, but not limited to, legends restricting the transfer of the Common Shares.

(h)                                 Withholding Obligations. Unless prohibited by the terms of an Award Agreement, the Company may, in its sole discretion, satisfy any federal, foreign, state, provincial or local tax withholding obligation relating to an Award by any of the following means or by a combination of such means: (i) causing the Participant to tender a cash payment; (ii) withholding Common Shares from the Common Shares issued or otherwise issuable to the Participant in connection with the Share Award; provided, however, that no Common Shares are withheld with a value exceeding the maximum amount of tax required to be withheld by law (or such lesser amount as may be necessary to avoid classification of the Share Award as a liability for financial accounting purposes); (iii) withholding cash from an Award settled in cash; (iv) withholding payment from any amounts otherwise payable to the Participant; or (v) by such other method as may be set forth in the Award Agreement.

(i)                                    Electronic Delivery. Any reference herein to a “written” agreement or document will include any agreement or document delivered electronically, filed publicly at www.sec.gov (or any successor website thereto) or posted on the Company’s intranet (or other shared electronic medium controlled by the Company to which the Participant has access).

(j)                                    Deferrals. To the extent permitted by applicable law, the Board, in its sole discretion, may determine that the delivery of Common Shares or the payment of cash, upon the exercise, vesting or settlement of all or a portion of any Award may be deferred and may establish programs and procedures for deferral elections to be made by Participants. Deferrals by Participants will be made in accordance with Section 409A of the Code or the Tax Act, as applicable. Consistent with Section 409A of the Code or the Tax Act, as applicable, the Board may provide for distributions while a Participant is still an employee or otherwise providing services to the Company. The Board is authorized to make deferrals of Awards and determine when, and in what annual percentages, Participants may receive payments, including lump sum payments, following the Participant’s termination of Continuous Service, and implement such other terms and conditions consistent with the provisions of the Plan and in accordance with applicable law.

(k)                                 Clawback/Recovery. All Awards granted under the Plan will be subject to recoupment in accordance with any clawback policy that the Company is required to adopt pursuant to the listing standards of any national securities exchange or association on which the Company’s securities are listed or as is otherwise required by the Dodd-Frank Wall Street Reform and Consumer Protection Act or other applicable law. In addition, the Board may impose such other clawback, recovery or recoupment provisions in an Award Agreement as the Board determines necessary or appropriate, including but not limited to a reacquisition right in respect of previously acquired Common Shares or other cash or property upon the occurrence of an event constituting Cause. No recovery of compensation under such a clawback policy will be an event giving rise to a right to voluntary terminate employment upon a “resignation for good reason,” or for a “constructive termination” or any similar term under any plan of or agreement with the Company.

(l)                                    Compliance with Section 409A of the Code. Unless otherwise expressly provided for in an Award Agreement, to the extent applicable, the Plan and Award Agreements will be interpreted to the greatest extent possible in a manner that makes the Plan and the Awards granted hereunder exempt from Section 409A of the Code, and, to the extent not so exempt, in compliance with Section 409A of the Code.

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To the extent Section 409A of the Code is applicable, if the Board determines that any Award granted hereunder is not exempt from and is therefore subject to Section 409A of the Code, the Award Agreement evidencing such Award will incorporate the terms and conditions necessary to avoid the consequences specified in Section 409A(a)(1) of the Code, and to the extent an Award Agreement is silent on terms necessary for compliance, such terms are hereby incorporated by reference into the Award Agreement. Notwithstanding anything to the contrary in this Plan (and unless the Award Agreement specifically provides otherwise), if the Common Shares are publicly traded, and if a Participant holding an Award that constitutes “deferred compensation” under Section 409A of the Code is a “specified employee” for purposes of Section 409A of the Code, no distribution or payment of any amount that is due because of a “separation from service” (as defined in Section 409A of the Code without regard to alternative definitions thereunder) will be issued or paid before the date that is six months following the date of such Participant’s “separation from service” or, if earlier, the date of the Participant’s death, unless such distribution or payment can be made in a manner that complies with Section 409A of the Code, and any amounts so deferred will be paid in a lump sum on the day after such six month period elapses, with the balance paid thereafter on the original schedule.

9.                                      ADJUSTMENTS UPON CHANGES IN COMMON SHARES; OTHER CORPORATE EVENTS.

(a)                                 Capitalization Adjustments. In the event of a Capitalization Adjustment, the Board will appropriately and proportionately adjust: (i) the class(es) and maximum number of securities subject to the Plan pursuant to Section 3(a), (ii) the class(es) and maximum number of securities by which the share reserve is to increase automatically each year pursuant to Section 3(a), (iii) the class(es) and maximum number of securities that may be issued pursuant to the exercise of Incentive Stock Options pursuant to Section 3(c), (iv) the class(es) and maximum number of securities that may be awarded to any Non-Employee Director pursuant to Section 3(d), and (v) the class(es) and number of securities and price per share subject to outstanding Share Awards. The Board will make such adjustments, and its determination will be final, binding and conclusive.

(b)                                 Dissolution. Except as otherwise provided in the Share Award Agreement, in the event of a Dissolution of the Company, all outstanding Share Awards (other than Share Awards consisting of vested and outstanding Common Shares not subject to a forfeiture condition or the Company’s right of repurchase) will terminate immediately prior to the completion of such Dissolution, and the Common Shares subject to the Company’s repurchase rights or subject to a forfeiture condition may be repurchased or reacquired by the Company notwithstanding the fact that the holder of such Share Award is providing Continuous Service; provided, however, that the Board may, in its sole discretion, cause some or all Share Awards to become fully vested, exercisable and/or no longer subject to repurchase or forfeiture (to the extent such Share Awards have not previously expired or terminated) before the Dissolution is completed but contingent on its completion.

(c)                                  Transaction. The following provisions will apply to Share Awards in the event of a Transaction unless otherwise provided in the Share Award Agreement or any other written agreement between the Company or any Affiliate and the Participant or unless otherwise expressly provided by the Board at the time of grant of a Share Award. In the event of a Transaction, then, notwithstanding any other provision of the Plan, the Board may take one or more of the following actions with respect to Share Awards, contingent upon the closing or completion of the Transaction:

(i)                                    arrange for the surviving corporation or acquiring corporation (or the surviving or acquiring corporation’s parent company) to assume or continue the Share Award or to substitute a similar share award for the Share Award (including, but not limited to, an award to acquire the same consideration paid to the shareholders of the Company pursuant to the Transaction);

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(ii)                                arrange for the assignment of any reacquisition or repurchase rights held by the Company in respect of Common Shares issued pursuant to the Share Award to the surviving corporation or acquiring corporation (or the surviving or acquiring corporation’s parent company);

(iii)                            accelerate the vesting, in whole or in part, of the Share Award (and, if applicable, the time at which the Share Award may be exercised) to a date prior to the effective time of such Transaction as the Board determines (or, if the Board does not determine such a date, to the date that is five days prior to the effective date of the Transaction), with such Share Award terminating if not exercised (if applicable) at or prior to the effective time of the Transaction; provided, however, that the Board may require Participants to complete and deliver to the Company a notice of exercise before the effective date of a Transaction, which exercise is contingent upon the effectiveness of such Transaction;

(iv)                             arrange for the lapse, in whole or in part, of any reacquisition or repurchase rights held by the Company with respect to the Share Award;

(v)                                 cancel or arrange for the cancellation of the Share Award, to the extent not vested or not exercised prior to the effective time of the Transaction, in exchange for such cash consideration, if any, as the Board, in its sole discretion, may consider appropriate; and

(vi)                             make a payment, in such form as may be determined by the Board equal to the excess, if any, of (A) the value of the property the Participant would have received upon the exercise of the Share Award immediately prior to the effective time of the Transaction, over (B) any exercise price payable by such holder in connection with such exercise. For clarity, this payment may be $0 if the value of the property is equal to or less than the exercise price. Payments under this provision may be delayed to the same extent that payment of consideration to the holders of the Company’s Common Shares in connection with the Transaction is delayed as a result of escrows, earn outs, holdbacks or any other contingencies.

The Board need not take the same action or actions with respect to all Share Awards or portions thereof or with respect to all Participants. The Board may take different actions with respect to the vested and unvested portions of a Share Award.

(d)                                 Change in Control. A Share Award may be subject to additional acceleration of vesting and exercisability upon or after a Change in Control as may be provided in the Share Award Agreement for such Share Award or as may be provided in any other written agreement between the Company or any Affiliate and the Participant, but in the absence of such provision, no such acceleration will occur.

10.                               PLAN TERM; EARLIER TERMINATION OR SUSPENSION OF THE PLAN.

The Board may suspend or terminate the Plan at any time. No Incentive Stock Options may be granted after the tenth anniversary of the earlier of (i) the date the Plan is adopted by the Board (the “Adoption Date”), or (ii) the date the Plan is approved by the shareholders of the Company. No Awards may be granted under the Plan while the Plan is suspended or after it is terminated.

11.                               EXISTENCE OF THE PLAN; TIMING OF FIRST GRANT OR EXERCISE.

The Plan will come into existence on the Adoption Date; provided, however, that no Share Award may be granted prior to the IPO Date. In addition, no Share Award will be exercised (or, in the case of a Restricted Share Award, Restricted Share Unit Award, Performance Share Award, or Other Share Award, no Share Award will be granted) and no Performance Cash Award will be settled unless and until the Plan has been approved by the shareholders of the Company, which approval will be within 12 months after the date the Plan is adopted by the Board.

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12.                               CHOICE OF LAW.

The laws of the province of Quebec and the laws of Canada applicable therein will govern all questions concerning the construction, validity and interpretation of this Plan.

13.                               DEFINITIONS. As used in the Plan, the following definitions will apply to the capitalized terms indicated below:

(a)                                 “Affiliate” means, at the time of determination, any “parent” or “subsidiary” of the Company as such terms are defined in Rule 405 of the Securities Act. The Board will have the authority to determine the time or times at which “parent” or “subsidiary” status is determined within the foregoing definition.

(b)                                 “Award” means a Share Award or a Performance Cash Award.

(c)                                  “Award Agreement” means a written agreement between the Company and a Participant evidencing the terms and conditions of an Award.

(d)                                 “Board” means the Board of Directors of the Company.

(e)                                  “Capital Shares” means each and every class of common shares of the Company, regardless of the number of votes per share.

(f)                                   “Capitalization Adjustment” means any change that is made in, or other events that occur with respect to, the Common Shares subject to the Plan or subject to any Share Award after the Adoption Date without the receipt of consideration by the Company through merger, amalgamation, arrangement, consolidation, reorganization, recapitalization, reincorporation, share dividend, dividend in property other than cash, large nonrecurring cash dividend, share split, reverse share split, liquidating dividend, combination of shares, exchange of shares, change in corporate structure or any similar equity restructuring transaction, as that term is used in Statement of Financial Accounting Standards Board Accounting Standards Codification Topic 718 (or any successor thereto). Notwithstanding the foregoing, the conversion of any convertible securities of the Company will not be treated as a Capitalization Adjustment.

(g)                                 “Cause” shall have the meaning ascribed to such term in any written agreement between the Participant and the Company or an Affiliate defining such term and, in the absence of such agreement, such term means, with respect to a Participant, in addition to such meaning as shall have been or shall hereafter be ascribed to such term or similar terms from time to time by the jurisprudence or law: (i) a failure or refusal by the Participant to perform his or her customary duties or services for the Company or any Affiliate without lawful justification after being provided with 10 business days’ notice from the Company and an opportunity to cure such failure to perform, in a manner satisfactory to the Company or any Affiliate; (ii) the Participant’s conviction for a criminal act or other indictable offence pursuant to the provisions of the Criminal Code or of any other criminal or penal statute of any jurisdiction which the Company or any Affiliate reasonably determines may have an adverse effect upon the reputation or good will of the Company or any Affiliate or on the performance of the Participant’s duties, or the commission by the Participant of any indictable or criminal offence or act which denotes moral turpitude, whether relating or not to the course of employment; (iii) a breach by the Participant of, or his or her failure or refusal to perform, in any material respect, any of his or her obligations under any employment agreement, employee invention and confidentiality agreement or such other material written agreement between participant and the company or any related entity; (iv) wanting in adequate capacity or qualification to fulfil the Participant’s employment functions; (v) any breach of any non-compete or non-solicitation covenant of the participant; or (vi) any dishonest or fraudulent act relating directly or indirectly to the course of

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employment. The determination that a termination of the Participant’s Continuous Service is either for Cause or without Cause shall be made by the Company, in its sole discretion. Any determination by the Company that the Continuous Service of a Participant was terminated with or without Cause for the purposes of outstanding Awards held by such Participant shall have no effect upon any determination of the rights or obligations of the Company or such Participant for any other purpose.

(h)                                 “Change in Control” means the occurrence, in a single transaction or in a series of related transactions, of any one or more of the following events:

(i)                                    any Exchange Act Person becomes the Owner, directly or indirectly, of securities of the Company representing more than 50% of the combined voting power of the Company’s then outstanding securities other than by virtue of a merger, amalgamation, arrangement, consolidation or similar transaction. Notwithstanding the foregoing, a Change in Control will not be deemed to occur (A) on account of the acquisition of securities of the Company directly from the Company, (B) on account of the acquisition of securities of the Company by an investor, any affiliate thereof or any other Exchange Act Person that acquires the Company’s securities in a transaction or series of related transactions the primary purpose of which is to obtain financing for the Company through the issuance of equity securities, (C) on account of the acquisition of securities of the Company by any individual who is, on the IPO Date, either an executive officer or a Director (either, an “IPO Investor”) and/or any entity in which an IPO Investor has a direct or indirect interest (whether in the form of voting rights or participation in profits or capital contributions) of more than 50% (collectively, the “IPO Entities”) or on account of the IPO Entities continuing to hold shares that come to represent more than 50% of the combined voting power of the Company’s then outstanding securities as a result of the conversion of any class of the Company’s securities into another class of the Company’s securities having a different number of votes per share pursuant to the conversion provisions set forth in the Company’s Amended and Restated Certificate of Incorporation; or (D) solely because the level of Ownership held by any Exchange Act Person (the “Subject Person”) exceeds the designated percentage threshold of the outstanding voting securities as a result of a repurchase or other acquisition of voting securities by the Company reducing the number of shares outstanding, provided that if a Change in Control would occur (but for the operation of this sentence) as a result of the acquisition of voting securities by the Company, and after such share acquisition, the Subject Person becomes the Owner of any additional voting securities that, assuming the repurchase or other acquisition had not occurred, increases the percentage of the then outstanding voting securities Owned by the Subject Person over the designated percentage threshold, then a Change in Control will be deemed to occur;

(ii)                                there is consummated a merger, amalgamation, arrangement, consolidation or similar transaction involving (directly or indirectly) the Company and, immediately after the consummation of such merger, amalgamation, arrangement, consolidation or similar transaction, the shareholders of the Company immediately prior thereto do not Own, directly or indirectly, either (A) outstanding voting securities representing more than 50% of the combined outstanding voting power of the surviving Entity in such merger, amalgamation, arrangement, consolidation or similar transaction or (B) more than 50% of the combined outstanding voting power of the parent of the surviving Entity in such merger, amalgamation, arrangement, consolidation or similar transaction, in each case in substantially the same proportions as their Ownership of the outstanding voting securities of the Company immediately prior to such transaction; provided, however, that a merger, amalgamation, arrangement, consolidation or similar transaction will not constitute a Change in Control under this prong of the definition if the outstanding voting securities representing more than 50% of the combined voting power of the surviving Entity or its parent are owned by the IPO Entities;

(iii)                            there is consummated a sale, lease, exclusive license or other disposition of all or substantially all of the consolidated assets of the Company and its Subsidiaries, other than a sale, lease, license or other disposition of all or substantially all of the consolidated assets of the Company and its

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Subsidiaries to an Entity, more than 50% of the combined voting power of the voting securities of which are Owned by shareholders of the Company in substantially the same proportions as their Ownership of the outstanding voting securities of the Company immediately prior to such sale, lease, license or other disposition; provided, however, that a sale, lease, exclusive license or other disposition of all or substantially all of the consolidated assets of the Company and its Subsidiaries will not constitute a Change in Control under this prong of the definition if the outstanding voting securities representing more than 50% of the combined voting power of the acquiring Entity or its parent are owned by the IPO Entities;

(iv)                             the shareholders of the Company approve or the Board approves a plan of complete dissolution or liquidation of the Company, or a complete dissolution or liquidation of the Company will otherwise occur, except for a liquidation into a parent corporation; or

(v)                                 individuals who, on the IPO Date, are members of the Board (the “Incumbent Board”) cease for any reason to constitute at least a majority of the members of the Board; provided, however, that if the appointment or election (or nomination for election) of any new Board member was approved or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member will, for purposes of this Plan, be considered as a member of the Incumbent Board.

Notwithstanding the foregoing definition or any other provision of the Plan, (A) the term Change in Control will not include a sale of assets, merger amalgamation, arrangement, or other transaction effected exclusively for the purpose of changing the domicile of the Company and the definition of Change in Control (or any analogous term) in an individual written agreement between the Company or any Affiliate and the Participant will supersede the foregoing definition with respect to Awards subject to such agreement; provided, however, that if no definition of Change in Control or any analogous term is set forth in such an individual written agreement, the foregoing definition will apply.

(i)                                    “Code” means the Internal Revenue Code of 1986, as amended, including any applicable regulations and guidance thereunder.

(j)                                    “Committee” means a committee of one or more Directors to whom authority has been delegated by the Board in accordance with Section 2(c).

(k)                                 “Common Share” means, as of the IPO Date, a common share in the share capital of the Company.

(l)                                    “Company” means Milestone Pharmaceuticals Inc and any successor corporation thereto.

(m)                             “Consultant” means any person, including an advisor, who is (i) engaged by the Company or an Affiliate to render consulting or advisory services and is compensated for such services, or (ii) serving as a member of the board of directors of an Affiliate and is compensated for such services. However, service solely as a Director, or payment of a fee for such service, will not cause a Director to be considered a “Consultant” for purposes of the Plan. Notwithstanding the foregoing, a person is treated as a Consultant under this Plan only if a Form S-8 Registration Statement under the Securities Act is available to register either the offer or the sale of the Company’s securities to such person.

(n)                                 “Continuous Service” means that the Participant’s service with the Company or an Affiliate, whether as an Employee, Director or Consultant, is not interrupted or terminated. A change in the capacity in which the Participant renders service to the Company or an Affiliate as an Employee, Consultant or Director or a change in the entity for which the Participant renders such service, provided that there is no interruption or termination of the Participant’s service with the Company or an Affiliate, will not

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terminate a Participant’s Continuous Service; provided, however, that if the Entity for which a Participant is rendering services ceases to qualify as an Affiliate, as determined by the Board, in its sole discretion, such Participant’s Continuous Service will be considered to have terminated on the date such Entity ceases to qualify as an Affiliate. To the extent permitted by law, the Board or the chief executive officer of the Company, in that party’s sole discretion, may determine whether Continuous Service will be considered interrupted in the case of (i) any leave of absence approved by the Board or chief executive officer, including sick leave, military leave or any other personal leave, or (ii) transfers between the Company, an Affiliate, or their successors. Notwithstanding the foregoing, a leave of absence will be treated as Continuous Service for purposes of vesting in an Award only to such extent as may be provided in the Company’s leave of absence policy, in the written terms of any leave of absence agreement or policy applicable to the Participant, or as otherwise required by law.

(o)                                 “Corporate Transaction” means the consummation, in a single transaction or in a series of related transactions, of any one or more of the following events:

(i)                                    a sale or other disposition of all or substantially all, as determined by the Board, in its sole discretion, of the consolidated assets of the Company and its Subsidiaries;

(ii)                                a sale or other disposition of more than 50% of the outstanding securities of the Company;

(iii)                            a merger, amalgamation, arrangement, consolidation or similar transaction following which the Company is not the surviving corporation; or

(iv)                             a merger, amalgamation, arrangement, consolidation or similar transaction following which the Company is the surviving corporation but the Common Shares outstanding immediately preceding the merger, consolidation or similar transaction are converted or exchanged by virtue of the merger, amalgamation, arrangement, consolidation or similar transaction into other property, whether in the form of securities, cash or otherwise.

(p)                                 “Director” means a member of the Board.

(q)                                 “Disability” means, with respect to a Participant, the inability of such Participant to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment that can be expected to result in death or that has lasted or can be expected to last for a continuous period of not less than 12 months, as provided in Sections 22(e)(3) and 409A(a)(2)(c)(i) of the Code, and will be determined by the Board on the basis of such medical evidence as the Board deems warranted under the circumstances.

(r)                                  “Dissolution” means when the Company, after having executed a certificate of dissolution with the Registraire des entreprises du Quebec, has completely wound up its affairs.

(s)                                   “Employee” means any person employed by the Company or an Affiliate. However, service solely as a Director, or payment of a fee for such services, will not cause a Director to be considered an “Employee” for purposes of the Plan.

(t)                                    “Entity” means a corporation, partnership, limited liability company or other entity.

(u)                                 “Exchange Act” means the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder.

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(v)                                 “Exchange Act Person” means any natural person, Entity or “group” (within the meaning of Section 13(d) or 14(d) of the Exchange Act), except that “Exchange Act Person” will not include (i) the Company or any Subsidiary of the Company, (ii) any employee benefit plan of the Company or any Subsidiary of the Company or any trustee or other fiduciary holding securities under an employee benefit plan of the Company or any Subsidiary of the Company, (iii) an underwriter temporarily holding securities pursuant to a registered public offering of such securities, (iv) an Entity Owned, directly or indirectly, by the shareholders of the Company in substantially the same proportions as their Ownership of shares of the Company; or (v) any natural person, Entity or “group” (within the meaning of Section 13(d) or 14(d) of the Exchange Act) that, as of the IPO Date, is the Owner, directly or indirectly, of securities of the Company representing more than 50% of the combined voting power of the Company’s then outstanding securities.

(w)                               “Fair Market Value” means, as of any date, the value of the Common Shares determined as follows:

(i)                                    If the Common Shares are listed on any established stock exchange or traded on any established market, the Fair Market Value of a Common Share will be, unless otherwise determined by the Board, the closing sales price for such share as quoted on such exchange or market (or the exchange or market with the greatest volume of trading in the Common Shares) on the date of determination, as reported in a source the Board deems reliable.

(ii)                                Unless otherwise provided by the Board, if there is no closing sales price for the Common Shares on the date of determination, then the Fair Market Value will be the closing selling price on the last preceding date for which such quotation exists.

(iii)                            In the absence of such markets for the Common Shares, the Fair Market Value will be determined by the Board in good faith and in a manner that complies with Sections 409A and 422 of the Code.

(x)                                 “Incentive Stock Option” means an option granted pursuant to Section 5 of the Plan that is intended to be, and qualifies as, an “incentive stock option” within the meaning of Section 422 of the Code.

(y)                                 “IPO Date” means the date of the underwriting agreement between the Company and the underwriter(s) managing the initial public offering of the Common Shares, pursuant to which the Common Shares are priced for the initial public offering.

(z)                                  “Non-Employee Director” means a Director who either (i) is not a current employee or officer of the Company or an Affiliate, does not receive compensation, either directly or indirectly, from the Company or an Affiliate for services rendered as a consultant or in any capacity other than as a Director (except for an amount as to which disclosure would not be required under Item 404(a) of Regulation S-K promulgated pursuant to the Securities Act (“Regulation S-K”)), does not possess an interest in any other transaction for which disclosure would be required under Item 404(a) of Regulation S-K, and is not engaged in a business relationship for which disclosure would be required pursuant to Item 404(b) of Regulation S-K; or (ii) is otherwise considered a “non-employee director” for purposes of Rule 16b-3.

(aa)                          “Nonstatutory Stock Option” means any Option granted pursuant to Section 5 of the Plan that does not qualify as an Incentive Stock Option.

(bb)                          “Officer” means a person who is an officer of the Company within the meaning of Section 16 of the Exchange Act.

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(cc)                            “Option” means an Incentive Stock Option or a Nonstatutory Stock Option to purchase Common Shares granted pursuant to the Plan.

(dd)                          “Option Agreement” means a written agreement between the Company and an Optionholder evidencing the terms and conditions of an Option grant. Each Option Agreement will be subject to the terms and conditions of the Plan.

(ee)                            “Optionholder” means a person to whom an Option is granted pursuant to the Plan or, if applicable, such other person who holds an outstanding Option.

(ff)                              “Other Share Award” means an award based in whole or in part by reference to the Common Shares which is granted pursuant to the terms and conditions of Section 6(d).

(gg)                          “Other Share Award Agreement” means a written agreement between the Company and a holder of an Other Share Award evidencing the terms and conditions of an Other Share Award grant. Each Other Share Award Agreement will be subject to the terms and conditions of the Plan.

(hh)                          “Own,” “Owned,” “Owner,” “Ownership” means a person or Entity will be deemed to “Own,” to have “Owned,” to be the “Owner” of, or to have acquired “Ownership” of securities if such person or Entity, directly or indirectly, through any contract, arrangement, understanding, relationship or otherwise, has or shares voting power, which includes the power to vote or to direct the voting, with respect to such securities.

(ii)                                “Participant” means a person to whom an Award is granted pursuant to the Plan or, if applicable, such other person who holds an outstanding Award.

(jj)                                “Performance Cash Award” means an award of cash granted pursuant to the terms and conditions of Section 6(c)(ii).

(kk)                          “Performance Criteria” means the one or more criteria that the Board will select for purposes of establishing the Performance Goals for a Performance Period. The Performance Criteria that will be used to establish such Performance Goals may be based on any one of, or combination of, the following as determined by the Board: (i) sales; (ii) revenues; (iii) assets; (iv) expenses; (v) market penetration or expansion; (vi) earnings from operations; (vii) earnings before or after deduction for all or any portion of interest, taxes, depreciation, amortization, incentives, service fees or extraordinary or special items, whether or not on a continuing operations or an aggregate or per share basis; (viii) net income or net income per common share (basic or diluted); (ix) return on equity, investment, capital or assets; (x) one or more operating ratios; (xi) borrowing levels, leverage ratios or credit rating; (xii) market share; (xiii) capital expenditures; (xiv) cash flow, free cash flow, cash flow return on investment, or net cash provided by operations; (xv) share price, dividends or total shareholder return; (xvi) development of new technologies or products; (xvii) sales of particular products or services; (xviii) economic value created or added; (xix) operating margin or profit margin; (xx) customer acquisition or retention; (xxi) raising or refinancing of capital; (xxii) successful hiring of key individuals; (xxiii) resolution of significant litigation; (xxiv) acquisitions and divestitures (in whole or in part); (xxv) joint ventures and strategic alliances; (xxvi) spin-offs, split-ups and the like; (xxvii) reorganizations; (xxviii) recapitalizations, restructurings, financings (issuance of debt or equity) or refinancings; (xxix) or strategic business criteria, consisting of one or more objectives based on the following goals: achievement of timely development, design management or enrollment, meeting specified market penetration or value added, payor acceptance, patient adherence, peer reviewed publications, issuance of new patents, establishment of or securing of licenses to intellectual property, product development or introduction (including, without limitation, any clinical trial accomplishments, regulatory or other filings, approvals or milestones, discovery of novel products,

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maintenance of multiple products in pipeline, product launch or other product development milestones), geographic business expansion, cost targets, cost reductions or savings, customer satisfaction, operating efficiency, acquisition or retention, employee satisfaction, information technology, corporate development (including, without limitation, licenses, innovation, research or establishment of third party collaborations), manufacturing or process development, legal compliance or risk reduction, patent application or issuance goals, or goals relating to acquisitions, divestitures or other business combinations (in whole or in part), joint ventures or strategic alliances; and (xxx) other measures of performance selected by the Board.

(ll)                                “Performance Goals” means, for a Performance Period, the one or more goals established by the Board for the Performance Period based upon the Performance Criteria. Performance Goals may be based on a Company-wide basis, with respect to one or more business units, divisions, Affiliates, or business segments, and in either absolute terms or relative to the performance of one or more comparable companies or the performance of one or more relevant indices. The Board is authorized at any time in its sole discretion, to adjust or modify the calculation of a Performance Goal for such Performance Period in order to prevent the dilution or enlargement of the rights of Participants, (a) in the event of, or in anticipation of, any unusual or extraordinary corporate item, transaction, event or development; (b) in recognition of, or in anticipation of, any other unusual or nonrecurring events affecting the Company, or the financial statements of the Company in response to, or in anticipation of, changes in applicable laws, regulations, accounting principles, or business conditions; or (c) in view of the Board’s assessment of the business strategy of the Company, performance of comparable organizations, economic and business conditions, and any other circumstances deemed relevant. Specifically, the Board is authorized to make adjustment in the method of calculating attainment of Performance Goals and objectives for a Performance Period as follows: (i) to exclude the dilutive effects of acquisitions or joint ventures; (ii) to assume that any business divested by the Company achieved performance objectives at targeted levels during the balance of a Performance Period following such divestiture; and (iii) to exclude the effect of any change in the outstanding Common Shares of the Company by reason of any share dividend or split, share repurchase, reorganization, recapitalization, merger, consolidation, spin-off, combination or exchange of shares or other similar corporate change, or any distributions to common shareholders other than regular cash dividends. In addition, the Board is authorized to make adjustment in the method of calculating attainment of Performance Goals and objectives for a Performance Period as follows: (i) to exclude restructuring and/or other nonrecurring charges; (ii) to exclude exchange rate effects, as applicable, for non-U.S. dollar denominated net sales and operating earnings; (iii) to exclude the effects of changes to generally accepted accounting standards required by the Financial Accounting Standards Board; (iv) to exclude the effects of any items that are “unusual” in nature or occur “infrequently” as determined under generally accepted accounting principles; (v) to exclude the effects to any statutory adjustments to corporate tax rates; and (vi) to make other appropriate adjustments determined by the Board.

(mm)                  “Performance Period” means the period of time selected by the Board over which the attainment of one or more Performance Goals will be measured for the purpose of determining a Participant’s right to and the payment of a Share Award or a Performance Cash Award. Performance Periods may be of varying and overlapping duration, at the sole discretion of the Board.

(nn)                          “Performance Share Award” means a Share Award granted under the terms and conditions of Section 6(c)(i).

(oo)                          “Plan” means this Milestone Pharmaceuticals Inc. 2019 Equity Incentive Plan.

(pp)                          “Restricted Share Award” means an award of Common Shares which is granted pursuant to the terms and conditions of Section 6(a).

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(qq)                          “Restricted Share Award Agreement” means a written agreement between the Company and a holder of a Restricted Share Award evidencing the terms and conditions of a Restricted Share Award grant. Each Restricted Share Award Agreement will be subject to the terms and conditions of the Plan.

(rr)                            “Restricted Share Unit Award” means a right to receive Common Shares which is granted pursuant to the terms and conditions of Section 6(b).

(ss)                              “Restricted Share Unit Award Agreement” means a written agreement between the Company and a holder of a Restricted Share Unit Award evidencing the terms and conditions of a Restricted Share Unit Award grant. Each Restricted Share Unit Award Agreement will be subject to the terms and conditions of the Plan.

(tt)                                “Rule 16b-3” means Rule 16b-3 promulgated under the Exchange Act or any successor to Rule 16b-3, as in effect from time to time.

(uu)                          “Securities Act” means the Securities Act of 1933, as amended.

(vv)                          “Share Appreciation Right” or “SAR” means a right to receive the appreciation on Common Shares that is granted pursuant to the terms and conditions of Section 5.

(ww)                      “Share Appreciation Right Agreement” means a written agreement between the Company and a holder of a Share Appreciation Right evidencing the terms and conditions of a Share Appreciation Right grant. Each Share Appreciation Right Agreement will be subject to the terms and conditions of the Plan.

(xx)                          “Share Award” means any right to receive Common Shares granted under the Plan, including an Incentive Stock Option, a Nonstatutory Stock Option, a Restricted Share Award, a Restricted Share Unit Award, a Share Appreciation Right, a Performance Share Award or any Other Share Award.

(yy)                          “Share Award Agreement” means a written agreement between the Company and a Participant evidencing the terms and conditions of a Share Award grant. Each Share Award Agreement will be subject to the terms and conditions of the Plan.

(zz)                            “Subsidiary” means, with respect to the Company, (i) any corporation of which more than 50% of the outstanding capital stock having ordinary voting power to elect a majority of the board of directors of such corporation (irrespective of whether, at the time, stock of any other class or classes of such corporation will have or might have voting power by reason of the happening of any contingency) is at the time, directly or indirectly, Owned by the Company, and (ii) any partnership, limited liability company or other entity in which the Company has a direct or indirect interest (whether in the form of voting or participation in profits or capital contribution) of more than 50%.

(aaa)                   “Tax Act” means the Income Tax Act (Canada), as amended, including any applicable regulations and guidance thereunder.

(bbb)                   “Ten Percent Shareholder” means a person who Owns (or is deemed to Own pursuant to Section 424(d) of the Code) shares possessing more than 10% of the total combined voting power of all classes of shares of the Company or any Affiliate.

(ccc)                      “Transaction” means a Corporate Transaction or a Change in Control.

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Exhibit 4.13

MILESTONE PHARMACEUTICALS INC.

2019 EMPLOYEE SHARE PURCHASE PLAN

ADOPTED BY THE BOARD OF DIRECTORS: APRIL 10, 2019

APPROVED BY THE SHAREHOLDERS: APRIL 29, 2019

IPO DATE: MAY 8, 2019

1.                                      GENERAL; PURPOSE.

(a)                                 The Plan provides a means by which Eligible Employees of the Company and certain Designated Companies may be given an opportunity to purchase Common Shares.  The Plan permits the Company to grant a series of Purchase Rights to Eligible Employees under an Employee Stock Purchase Plan.

(b)                                 The Company, by means of the Plan, seeks to retain the services of such Employees, to secure and retain the services of new Employees and to provide incentives for such persons to exert maximum efforts for the success of the Company and its Related Corporations and Affiliates.

(c)                                  The Plan includes two components: a 423 Component and a Non-423 Component.  The Company intends (but makes no undertaking or representation to maintain) the 423 Component to qualify as an Employee Stock Purchase Plan.  The provisions of the 423 Component, accordingly, will be construed in a manner that is consistent with the requirements of Section 423 of the Code.  In addition, this Plan authorizes grants of Purchase Rights under the Non-423 Component that do not meet the requirements of an Employee Stock Purchase Plan.  Except as otherwise provided in the Plan or determined by the Board, the Non-423 Component will operate and be administered in the same manner as the 423 Component.  In addition, the Company may make separate Offerings which vary in terms (provided that such terms are not inconsistent with the provisions of the Plan or the requirements of an Employee Stock Purchase Plan), and the Company will designate which Designated Company is participating in each separate Offering.

2.                                      ADMINISTRATION.

(a)                                 The Board will administer the Plan unless and until the Board delegates administration of the Plan to a Committee or Committees, as provided in Section 2(c).

(b)                                 The Board will have the power, subject to, and within the limitations of, the express provisions of the Plan:

(i)                                    To determine how and when Purchase Rights will be granted and the provisions of each Offering (which need not be identical).

(ii)                                To designate from time to time which Related Corporations will be eligible to participate in the Plan as Designated 423 Corporations or as Designated Non-423 Corporations, which Affiliates may be excluded from participation in the Plan, and which Designated Companies will participate in each separate Offering (to the extent that the Company makes separate Offerings).

(iii)                            To construe and interpret the Plan and Purchase Rights, and to establish, amend and revoke rules and regulations for its administration.  The Board, in the exercise of this power, may correct any defect, omission or inconsistency in the Plan, in a manner and to the extent it deems necessary or expedient to make the Plan fully effective.

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(iv)                             To settle all controversies regarding the Plan and Purchase Rights granted under the Plan.

(v)                                 To suspend or terminate the Plan at any time as provided in Section 12.

(vi)                             To amend the Plan at any time as provided in Section 12.

(vii)                         Generally, to exercise such powers and to perform such acts as it deems necessary or expedient to promote the best interests of the Company, its Related Corporations, and Affiliates and to carry out the intent that the 423 Component be treated as an Employee Stock Purchase Plan.

(viii)                     To adopt such rules, procedures and sub-plans relating to the operation and administration of the Plan as are necessary or appropriate under applicable local laws, regulations and procedures to permit or facilitate participation in the Plan by Employees who are foreign nationals or employed or located outside the United States.  Without limiting the generality of, but consistent with, the foregoing, the Board specifically is authorized to adopt rules, procedures, and sub-plans, which, if applicable to a Designated Non-423 Corporation, do not have to comply with the requirements of Section 423 of the Code, regarding, without limitation, eligibility to participate in the Plan, the definition of eligible “earnings,” handling and making of Contributions, establishment of bank or trust accounts to hold Contributions, payment of interest, conversion of local currency, obligations to pay payroll tax, determination of beneficiary designation requirements, withholding procedures and handling of share issuances, any of which may vary according to applicable requirements.

(c)                                  The Board may delegate some or all of the administration of the Plan to a Committee or Committees.  If administration is delegated to a Committee, the Committee will have, in connection with the administration of the Plan, the powers theretofore possessed by the Board that have been delegated to the Committee, including the power to delegate to a subcommittee any of the administrative powers the Committee is authorized to exercise (and references in this Plan and in any applicable Offering Document to the Board will thereafter be to the Committee or subcommittee), subject, however, to such resolutions, not inconsistent with the provisions of the Plan, as may be adopted from time to time by the Board.  Further, to the extent not prohibited by applicable law, the Board or Committee may, from time to time, delegate some or all of its authority under the Plan to other persons or groups of persons as it deems necessary, appropriate, or advisable under conditions or limitations that it may set at or after the time of the delegation.  The Board may retain the authority to concurrently administer the Plan with the Committee and may, at any time, revest in the Board some or all of the powers previously delegated.  Whether or not the Board has delegated administration of the Plan to a Committee, the Board will have the final power to determine all questions of policy and expediency that may arise in the administration of the Plan.

(d)                                 All determinations, interpretations and constructions made by the Board in good faith will not be subject to review by any person and will be final, binding and conclusive on all persons.

3.                                      COMMON SHARES SUBJECT TO THE PLAN.

(a)                                 Subject to the provisions of Section 11(a) relating to Capitalization Adjustments and the following sentence regarding the Evergreen Increase, the initial number of Common Shares that may be issued under the Plan shall equal                                       shares (the “Share Reserve”).  In addition, the Share Reserve will automatically increase on January 1st of each year for a period of up to ten (10) years, commencing on January 1, 2020 and ending on (and including) January 1, 2029 (each, an “Evergreen Date”), in an amount equal to the lesser of (i) one percent (1%) of the total number of Capital Shares outstanding on December 31st immediately preceding the applicable Evergreen Date, and (ii) 487,837 shares (the “Evergreen Increase”).  Notwithstanding the foregoing, the Board may act prior to the Evergreen Date of a given year

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to provide that there will be no Evergreen Increase for such year or that the Evergreen Increase for such year will be a lesser number of Common Shares than would otherwise occur pursuant to the preceding sentence.  For the avoidance of doubt, up to the maximum number of Common Shares reserved under this Section 3(a) may be used to satisfy purchases of Common Shares under the 423 Component and any remaining portion of such maximum number of shares may be used to satisfy purchases of Common Shares under the Non-423 Component.

(b)                                 If any Purchase Right granted under the Plan terminates without having been exercised in full, the Common Shares not purchased under such Purchase Right will again become available for issuance under the Plan.

(c)                                  The shares purchasable under the Plan will be shares of authorized but unissued Common Shares.

4.                                      GRANT OF PURCHASE RIGHTS; OFFERING.

(a)                                 The Board may from time to time grant or provide for the grant of Purchase Rights to Eligible Employees under an Offering (consisting of one or more Purchase Periods) on an Offering Date or Offering Dates selected by the Board.  Each Offering will be in such form and will contain such terms and conditions as the Board will deem appropriate, and, with respect to the 423 Component, will comply with the requirement of Section 423(b)(5) of the Code that all Employees granted Purchase Rights will have the same rights and privileges.  The terms and conditions of an Offering shall be incorporated by reference into the Plan and treated as part of the Plan.  The provisions of separate Offerings need not be identical, but each Offering will include (through incorporation of the provisions of this Plan by reference in the Offering Document or otherwise) the period during which the Offering will be effective, which period will not exceed 27 months beginning with the Offering Date, and the substance of the provisions contained in Sections 5 through 8, inclusive.

(b)                                 If a Participant has more than one Purchase Right outstanding under the Plan, unless he or she otherwise indicates in forms delivered to the Company or a third party designated by the Company (each, a “Company Designee”): (i) each form will apply to all of his or her Purchase Rights under the Plan, and (ii) a Purchase Right with a lower exercise price (or an earlier-granted Purchase Right, if different Purchase Rights have identical exercise prices) will be exercised to the fullest possible extent before a Purchase Right with a higher exercise price (or a later-granted Purchase Right if different Purchase Rights have identical exercise prices) will be exercised.

(c)                                  The Board will have the discretion to structure an Offering so that if the Fair Market Value of a Common Share on the first Trading Day of a new Purchase Period within that Offering is less than or equal to the Fair Market Value of a Common Share on the Offering Date for that Offering, then (i) that Offering will terminate immediately as of that first Trading Day, and (ii) the Participants in such terminated Offering will be automatically enrolled in a new Offering beginning on the first Trading Day of such new Purchase Period.

5.                                      ELIGIBILITY.

(a)                                 Purchase Rights may be granted only to Employees of the Company or, as the Board may designate in accordance with Section 2(b), to Employees of a Related Corporation or an Affiliate.  Except as provided in Section 5(b) or as required by applicable law, an Employee will not be eligible to be granted Purchase Rights unless, on the Offering Date, the Employee has been in the employ of the Company, a Related Corporation or an Affiliate, as the case may be, for such continuous period preceding such Offering Date as the Board may require, but in no event will the required period of continuous employment be equal

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to or greater than two years.  In addition, the Board may provide that no Employee will be eligible to be granted Purchase Rights under the Plan unless, on the Offering Date, such Employee’s customary employment with the Company, the Related Corporation, or the Affiliate, as applicable, is more than 20 hours per week and more than five months per calendar year or such other criteria as the Board may determine consistent with Section 423 of the Code with respect to the 423 Component and applicable laws.

(b)                                 The Board may provide that each person who, during the course of an Offering, first becomes an Eligible Employee will, on a date or dates specified in the Offering which coincides with the day on which such person becomes an Eligible Employee or which occurs thereafter, receive a Purchase Right under that Offering, which Purchase Right will thereafter be deemed to be a part of that Offering.  Such Purchase Right will have the same characteristics as any Purchase Rights originally granted under that Offering, as described herein, except that:

(i)                                    the date on which such Purchase Right is granted will be the “Offering Date” of such Purchase Right for all purposes, including determination of the exercise price of such Purchase Right;

(ii)                                the period of the Offering with respect to such Purchase Right will begin on its Offering Date and end coincident with the end of such Offering; and

(iii)                            the Board may provide that if such person first becomes an Eligible Employee within a specified period of time before the end of the Offering, he or she will not receive any Purchase Right under that Offering.

(c)                                  No Employee will be eligible for the grant of any Purchase Rights if, immediately after any such Purchase Rights are granted, such Employee owns shares possessing five percent or more of the total combined voting power or value of all classes of shares of the Company or of any Related Corporation.  For purposes of this Section 5(c), the rules of Section 424(d) of the Code will apply in determining the share ownership of any Employee, and shares which such Employee may purchase under all outstanding Purchase Rights and options will be treated as shares owned by such Employee.

(d)                                 As specified by Section 423(b)(8) of the Code, an Eligible Employee may be granted Purchase Rights only if such Purchase Rights, together with any other rights granted under all Employee Stock Purchase Plans of the Company and any Related Corporations or Affiliates, do not permit such Eligible Employee’s rights to purchase shares of the Company or any Related Corporation or Affiliates to accrue at a rate which, when aggregated, exceeds US$25,000 of Fair Market Value of such shares (determined at the time such rights are granted, and which, with respect to the Plan, will be determined as of their respective Offering Dates) for each calendar year in which such rights are outstanding at any time, subject to compliance with applicable laws.

(e)                                  Officers of the Company and any Designated Company, if they are otherwise Eligible Employees, will be eligible to participate in Offerings under the Plan.  Notwithstanding the foregoing, the Board may provide in an Offering that Employees who are highly compensated Employees within the meaning of Section 423(b)(4)(D) of the Code will not be eligible to participate.

(f)                                   Notwithstanding anything in this Section 5 to the contrary, in the case of an Offering under the Non-423 Component, an Eligible Employee (or group of Eligible Employees) may be excluded from participation in the Plan or an Offering if the Board has determined, in its sole discretion, that participation of such Eligible Employee(s) is not advisable or practical for any reason.

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6.                                      PURCHASE RIGHTS; PURCHASE PRICE.

(a)                                 On each Offering Date, each Eligible Employee, pursuant to an Offering made under the Plan, will be granted a Purchase Right to purchase up to that number of Common Shares (rounded down to the nearest whole share) purchasable either with a percentage or with a maximum dollar amount, as designated by the Board, but in either case not exceeding 15% of such Employee’s earnings (as defined by the Board in each Offering) during the period that begins on the Offering Date (or such later date as the Board determines for a particular Offering) and ends on the date stated in the Offering, which date will be no later than the end of the Offering.

(b)                                 The Board will establish one or more Purchase Dates during an Offering on which Purchase Rights granted for that Offering will be exercised and Common Shares will be purchased in accordance with such Offering.

(c)                                  In connection with each Offering made under the Plan, the Board may specify (i) a maximum number of Common Shares that may be purchased by any Participant on any Purchase Date during such Offering, (ii) a maximum aggregate number of Common Shares that may be purchased by all Participants pursuant to such Offering and/or (iii) a maximum aggregate number of Common Shares that may be purchased by all Participants on any Purchase Date under the Offering.  If the aggregate purchase of Common Shares issuable upon exercise of Purchase Rights granted under the Offering would exceed any such maximum aggregate number, then, in the absence of any Board action otherwise, a pro rata (based on each Participant’s accumulated Contributions) allocation of Common Shares (rounded down to the nearest whole share) available will be made in as nearly a uniform manner as will be practicable and equitable.

(d)                                 The purchase price of Common Shares acquired pursuant to Purchase Rights will be not less than the lesser of:

(i)                                    an amount equal to 85% of the Fair Market Value of the Common Shares on the Offering Date; or

(ii)                                an amount equal to 85% of the Fair Market Value of the Common Shares on the applicable Purchase Date.

7.                                      PARTICIPATION; WITHDRAWAL; TERMINATION.

(a)                                 An Eligible Employee may elect to authorize payroll deductions as the means of making Contributions by completing and delivering to the Company or Company Designee, within the time specified in the Offering, an enrollment form provided by the Company or Company Designee. The enrollment form will specify the amount of Contributions not to exceed the maximum amount specified by the Board. Each Participant’s Contributions will be credited to a bookkeeping account for such Participant under the Plan and will be deposited with the general funds of the Company except where applicable laws or regulations require that Contributions be deposited with a Company Designee or otherwise segregated.  If permitted in the Offering, a Participant may begin such Contributions with the first payroll occurring on or after the Offering Date (or, in the case of a payroll date that occurs after the end of the prior Offering but before the Offering Date of the next new Offering, Contributions from such payroll will be included in the new Offering).  If permitted in the Offering, a Participant may thereafter reduce (including to zero) or increase his or her Contributions.  If required under applicable laws or regulations or if specifically provided in the Offering, in addition to or instead of making Contributions by payroll deductions, a Participant may make Contributions through a payment by cash, check, or wire transfer prior to a Purchase Date, in a manner directed by the Company or a Company Designee.

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(b)                                 During an Offering, a Participant may cease making Contributions and withdraw from the Offering by delivering to the Company or a Company Designee a withdrawal form provided by the Company.  The Company may impose a deadline before a Purchase Date for withdrawing.  Upon such withdrawal, such Participant’s Purchase Right in that Offering will immediately terminate and the Company will distribute as soon as practicable to such Participant all of his or her accumulated but unused Contributions and such Participant’s Purchase Right in that Offering shall thereupon terminate.  A Participant’s withdrawal from that Offering will have no effect upon his or her eligibility to participate in any other Offerings under the Plan, but such Participant will be required to deliver a new enrollment form to participate in subsequent Offerings.

(c)                                  Unless otherwise required by applicable law, Purchase Rights granted pursuant to any Offering under the Plan will terminate immediately if the Participant either (i) is no longer an Employee for any reason or for no reason or (ii) is otherwise no longer eligible to participate.  In this regard, unless otherwise determined by the Board, a Participant whose employment transfers or whose employment terminates with an immediate rehire (with no break in service) by or between the Company and a Designated Company will not be treated as having terminated employment for purposes of participating in the Plan or an Offering; however, if a Participant transfers from an Offering under the 423 Component to an Offering under the Non-423 Component, the exercise of the Participant’s Purchase Right will be qualified under the 423 Component only to the extent such exercise complies with Section 423 of the Code.  If a Participant transfers from an Offering under the Non-423 Component to an Offering under the 423 Component, the exercise of the Purchase Right will remain non-qualified under the Non-423 Component.  In the event that a Participant’s Purchase Right is terminated under the Plan, the Company will distribute as soon as practicable to such individual all of his or her accumulated but unused Contributions.

(d)                                 During a Participant’s lifetime, Purchase Rights will be exercisable only by such Participant.  Purchase Rights are not transferable by a Participant, except by will, by the laws of descent and distribution, or, if permitted by the Company, by a beneficiary designation as described in Section 10.

(e)                                  Unless otherwise specified in the Offering or required by applicable law, the Company will have no obligation to pay interest on Contributions.

8.                                      EXERCISE OF PURCHASE RIGHTS.

(a)                                 On each Purchase Date, each Participant’s accumulated Contributions will be applied to the purchase of Common Shares (rounded down to the nearest whole share), up to the maximum number of Common Shares permitted by the Plan and the applicable Offering, at the purchase price specified in the Offering.  No fractional shares will be issued unless specifically provided for in the Offering.

(b)                                 Unless otherwise provided in the Offering, if any amount of accumulated Contributions remains in a Participant’s account after the purchase of Common Shares and such remaining amount is less than the amount required to purchase one Common Share on the final Purchase Date of an Offering, then such remaining amount will be held in such Participant’s account for the purchase of Common Shares under the next Offering under the Plan, unless such Participant withdraws from or is not eligible to participate in such Offering, in which case such amount will be distributed to such Participant after the final Purchase Date, without interest, unless the payment of interest is required by applicable laws.  If the amount of Contributions remaining in a Participant’s account after the purchase of Common Shares is at least equal to the amount required to purchase one whole Common Share on the final Purchase Date of an Offering, then such remaining amount will not roll over to the next Offering and will instead be distributed in full to such Participant after the final Purchase Date of such Offering without interest, unless the payment of interest is required by applicable laws.

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(c)                                  No Purchase Rights may be exercised to any extent unless the Common Shares to be issued upon such exercise under the Plan are covered by an effective registration statement pursuant to the Securities Act and the Plan is in material compliance with all applicable U.S. federal and state, foreign and other securities, exchange control and other laws applicable to the Plan.  If on a Purchase Date the Common Shares are not so registered or the Plan is not in such compliance, no Purchase Rights will be exercised on such Purchase Date, and the Purchase Date will be delayed until the Common Shares are subject to such an effective registration statement and the Plan is in material compliance, except that the Purchase Date will not be delayed more than 12 months and the Purchase Date will in no event be more than 27 months from the Offering Date.  If, on the Purchase Date, as delayed to the maximum extent permissible, the Common Shares are not registered and the Plan is not in material compliance with all applicable laws or regulations, as determined by the Company in its sole discretion, no Purchase Rights will be exercised and all accumulated but unused Contributions will be distributed as soon as practicable to the Participants without interest, unless the payment of interest is required by applicable laws.

9.                                      COVENANTS OF THE COMPANY.

The Company will seek to obtain from each U.S. federal or state, foreign or other regulatory commission or agency having jurisdiction over the Plan such authority as may be required to grant Purchase Rights and issue and sell Common Shares thereunder unless the Company determines, in its sole discretion, that doing so would cause the Company to incur costs that are unreasonable.  If, after commercially reasonable efforts, the Company is unable to obtain the authority that counsel for the Company deems necessary for the grant of Purchase Rights or the lawful issuance and sale of Common Shares under the Plan, and at a commercially reasonable cost, the Company will be relieved from any liability for failure to grant Purchase Rights and/or to issue and sell Common Shares upon exercise of such Purchase Rights.

10.                               DESIGNATION OF BENEFICIARY.

(a)                                 The Company may, but is not obligated to, permit a Participant to submit a form designating a beneficiary who will receive any Common Shares and/or Contributions from the Participant’s account under the Plan if the Participant dies before such shares and/or Contributions are delivered to the Participant.  The Company may, but is not obligated to, permit the Participant to change such designation of beneficiary. Any such designation and/or change must be on a form approved by the Company or as approved by the Company for use by a Company Designee.

(b)                                 If a Participant dies, in the absence of a valid beneficiary designation, the Company will deliver any Common Shares and/or Contributions to the executor or administrator of the estate of the Participant.  If no executor or administrator has been appointed (to the knowledge of the Company), the Company, in its sole discretion, may deliver such Common Shares and/or Contributions, without interest, unless the payment of interest is required by applicable laws, to the Participant’s spouse, dependents or relatives, or if no spouse, dependent or relative is known to the Company, then to such other person as the Company may designate.

11.                               ADJUSTMENTS UPON CHANGES IN COMMON SHARES; CORPORATE TRANSACTIONS.

(a)                                 In the event of a Capitalization Adjustment, the Board will appropriately and proportionately adjust: (i) the class(es) and maximum number of securities subject to the Plan pursuant to Section 3(a), (ii) the class(es) and maximum number of securities by which the share reserve is to increase automatically each year pursuant to Section 3(a), (iii) the class(es) and number of securities subject to, and the purchase price applicable to outstanding Offerings and Purchase Rights, and (iv) the class(es) and number of securities that are the subject of the purchase limits under each ongoing Offering.  The Board will make these adjustments, and its determination will be final, binding and conclusive.

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(b)                                 In the event of a Corporate Transaction, then: (i) any surviving corporation or acquiring corporation (or the surviving or acquiring corporation’s parent company) may assume or continue outstanding Purchase Rights or may substitute similar rights (including a right to acquire the same consideration paid to the shareholders in the Corporate Transaction) for outstanding Purchase Rights, or (ii) if any surviving or acquiring corporation (or its parent company) does not assume or continue such Purchase Rights or does not substitute similar rights for such Purchase Rights, then the Participants’ accumulated Contributions will be used to purchase Common Shares (rounded down to the nearest whole share) within ten business days prior to the Corporate Transaction under the outstanding Purchase Rights, and the Purchase Rights will terminate immediately after such purchase.

12.                               AMENDMENT, TERMINATION OR SUSPENSION OF THE PLAN.

(a)                                 The Board may amend the Plan at any time in any respect the Board deems necessary or advisable.  However, except as provided in Section 11(a) relating to Capitalization Adjustments, shareholder approval will be required for any amendment of the Plan for which shareholder approval is required by applicable laws, regulations or listing requirements, including any amendment that either (i) materially increases the number of Common Shares available for issuance under the Plan, (ii) materially expands the class of individuals eligible to become Participants and receive Purchase Rights, (iii) materially increases the benefits accruing to Participants under the Plan or materially reduces the price at which Common Shares may be purchased under the Plan, (iv) materially extends the term of the Plan, or (v) expands the types of awards available for issuance under the Plan, but in each of (i) through (v) above only to the extent shareholder approval is required by applicable laws, regulations, or listing requirements.

(b)                                 The Board may suspend or terminate the Plan at any time.  No Purchase Rights may be granted under the Plan while the Plan is suspended or after it is terminated.

(c)                                  Any benefits, privileges, entitlements and obligations under any outstanding Purchase Rights granted before an amendment, suspension or termination of the Plan will not be materially impaired by any such amendment, suspension or termination except (i) with the consent of the person to whom such Purchase Rights were granted, (ii) as necessary to comply with any laws, listing requirements, or governmental regulations (including, without limitation, the provisions of Section 423 of the Code and the regulations and other interpretive guidance issued thereunder relating to Employee Stock Purchase Plans) including without limitation any such regulations or other guidance that may be issued or amended after the Effective Date, or (iii) as necessary to obtain or maintain any special tax, listing, or regulatory treatment.  To be clear, the Board may amend outstanding Purchase Rights without a Participant’s consent if such amendment is necessary to ensure that the Purchase Right and/or the 423 Component complies with the requirements of Section 423 of the Code, or other applicable laws, listing requirements, or governmental regulations.

Notwithstanding anything in the Plan or any Offering Document to the contrary, the Board will be entitled to: (i) establish the exchange ratio applicable to amounts withheld in a currency other than U.S. dollars; (ii) permit Contributions in excess of the amount designated by a Participant in order to adjust for mistakes in the Company’s processing of properly completed Contribution elections; (iii) establish reasonable waiting and adjustment periods and/or accounting and crediting procedures to ensure that amounts applied toward the purchase of Common Shares for each Participant properly correspond with amounts withheld from the Participant’s Contributions; (iv) amend any outstanding Purchase Rights or clarify any ambiguities regarding the terms of any Offering to enable the Purchase Rights to qualify under and/or comply with Section 423 of the Code; and (v) establish other limitations or procedures as the Board determines in its sole discretion advisable that are consistent with the Plan. The actions of the Board pursuant to this paragraph will not be considered to alter or impair any Purchase Rights granted under an

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Offering as they are part of the initial terms of each Offering and the Purchase Rights granted under each Offering.

13.                               SECTION 409A OF THE CODE; TAX QUALIFICATION.

(a)                                 Purchase Rights granted under the 423 Component are intended to be exempt from the application of Section 409A of the Code under U.S. Treasury Regulation Section 1.409A-1(b)(5)(ii).  Purchase Rights granted under the Non-423 Component to U.S. taxpayers are intended to be exempt from the application of Section 409A of the Code under the short-term deferral exception and any ambiguities will be construed and interpreted in accordance with such intent.  Subject to Section 13(b) below, Purchase Rights granted to U.S. taxpayers under the Non-423 Component will be subject to such terms and conditions that will permit such Purchase Rights to satisfy the requirements of the short-term deferral exception available under Section 409A of the Code, including the requirement that the shares subject to a Purchase Right be delivered within the short-term deferral period.  Subject to Section 13(b) below, in the case of a Participant who would otherwise be subject to Section 409A of the Code, to the extent the Board determines that a Purchase Right or the exercise, payment, settlement or deferral thereof is subject to Section 409A of the Code, the Purchase Right will be granted, exercised, paid, settled or deferred in a manner that will comply with Section 409A of the Code, including U.S. Department of Treasury regulations and other interpretive guidance issued thereunder, including, without limitation, any such regulations or other guidance that may be issued after the adoption of the Plan.  Notwithstanding the foregoing, the Company will have no liability to a Participant or any other party if the Purchase Right that is intended to be exempt from or compliant with Section 409A of the Code is not so exempt or compliant or for any action taken by the Board with respect thereto.

(b)                                 Although the Company may endeavor to (i) qualify a Purchase Right for special tax treatment under the laws of the United States or jurisdictions outside of the United States or (ii) avoid adverse tax treatment (e.g., under Section 409A of the Code), the Company makes no representation to that effect and expressly disavows any covenant to maintain special or to avoid unfavorable tax treatment, notwithstanding anything to the contrary in this Plan, including Section 13(a) above.  The Company will be unconstrained in its corporate activities without regard to the potential negative tax impact on Participants under the Plan.

14.                               TAX WITHHOLDING

The Participant will make adequate provision to satisfy the Tax-Related Items withholding obligations, if any, of the Company and/or the applicable Designated Company which arise with respect to Participant’s participation in the Plan or upon the disposition of the Common Shares.  The Company and/or the Designated Company may, but will not be obligated to, withhold from the Participant’s compensation or any other payments due the Participant the amount necessary to meet such withholding obligations or withhold from the proceeds of the sale of Common Shares or any other method of withholding that the Company and/or the Designated Company deems appropriate. The Company and/or the Designated Company will have the right to take such other action as may be necessary in the opinion of the Company or a Designated Company to satisfy withholding and/or reporting obligations for such Tax-Related Items.

15.                               EFFECTIVE DATE OF PLAN.

The Plan will become effective immediately prior to and contingent upon the IPO Date.  No Purchase Rights will be exercised unless and until the Plan has been approved by the shareholders of the Company, which approval must be within 12 months before or after the date the Plan is adopted (or if required under Section 12(a) above, materially amended) by the Board.

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16.                               MISCELLANEOUS PROVISIONS.

(a)                                 Proceeds from the sale of Common Shares pursuant to Purchase Rights will constitute general funds of the Company.

(b)                                 A Participant will not be deemed to be the holder of, or to have any of the rights of a holder with respect to, Common Shares subject to Purchase Rights unless and until the Participant’s Common Shares acquired upon exercise of Purchase Rights are recorded in the books of the Company (or its transfer agent).

(c)                                  The Plan and Offering do not constitute an employment contract.  Nothing in the Plan or in the Offering will in any way alter the at-will nature of a Participant’s employment, if applicable, or be deemed to create in any way whatsoever any obligation on the part of any Participant to continue in the employ of the Company, a Related Corporation, or an Affiliate, or on the part of the Company, a Related Corporation or an Affiliate to continue the employment of a Participant.

(d)                                 The provisions of the Plan will be governed by the laws of the State of Delaware without resort to that state’s conflicts of laws rules.

(e)                                  If any particular provision of the Plan is found to be invalid or otherwise unenforceable, such provision will not affect the other provisions of the Plan, but the Plan will be construed in all respects as if such invalid provision were omitted.

(f)                                   The Company’s insider trading policy as in effect from time to time may be applicable to an Employee’s rights under the Plan.  Notwithstanding any Plan provision to the contrary, no Employee shall, while in possession of material undisclosed information, elect to enroll or elect to increase, decrease or cease Contributions.  The Board may require an Employee to acknowledge that such election is being made in compliance with the Company’s insider trading policy.

(g)                                 If any provision of the Plan does not comply with applicable law or regulations, such provision shall be construed in such a manner as to comply with applicable law or regulations.

17.                               DEFINITIONS.

As used in the Plan, the following definitions will apply to the capitalized terms indicated below:

(a)                                 “423 Component” means the part of the Plan, which excludes the Non-423 Component, pursuant to which Purchase Rights that satisfy the requirements for an Employee Stock Purchase Plan may be granted to Eligible Employees.

(b)                                 “Affiliate” means any entity, other than a Related Corporation, in which the Company has an equity or other ownership interest or that is directly or indirectly controlled by, controls, or is under common control with the Company, in all cases, as determined by the Board, whether now or hereafter existing.

(c)                                  “Board” means the board of directors of the Company.

(d)                                 “Capital Shares” means each and every class of common shares of the Company, regardless of the number of votes per share.

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(e)                                  “Capitalization Adjustment” means any change that is made in, or other events that occur with respect to, the Common Shares subject to the Plan or subject to any Purchase Right after the Effective Date without the receipt of consideration by the Company through merger, amalgamation, arrangement, consolidation, reorganization, recapitalization, reincorporation, share dividend, dividend in property other than cash, large nonrecurring cash dividend, share split, liquidating dividend, combination of shares, exchange of shares, change in corporate structure or other similar equity restructuring transaction, as that term is used in Financial Accounting Standards Board Accounting Standards Codification Topic 718 (or any successor thereto).  Notwithstanding the foregoing, the conversion of any convertible securities of the Company will not be treated as a Capitalization Adjustment.

(f)                                   “Code” means the U.S. Internal Revenue Code of 1986, as amended, including any applicable regulations and guidance thereunder.

(g)                                 “Committee” means a committee of one or more members of the Board to whom authority has been delegated by the Board in accordance with Section 2(c).

(h)                                 “Common Share” means, as of the IPO Date, a common share in the share capital of the Company.

(i)                                    “Company” means Milestone Pharmaceuticals Inc. and any successor corporation thereto.

(j)                                    “Contributions” means the payroll deductions and/or other payments specifically provided for in the Offering that a Participant contributes to fund the exercise of a Purchase Right. A Participant may make additional payments into his or her account if specifically provided for in the Offering, and then only if the Participant has not already contributed the maximum permitted amount of payroll deductions and/or other payments during the Offering.

(k)                                 “Corporate Transaction” means the consummation, in a single transaction or in a series of related transactions, of any one or more of the following events:

(i)                                    a sale or other disposition of all or substantially all, as determined by the Board in its sole discretion, of the consolidated assets of the Company and its Subsidiaries;

(ii)                                a sale or other disposition of more than 50% of the outstanding securities of the Company;

(iii)                            a merger, amalgamation, arrangement, consolidation or similar transaction following which the Company is not the surviving corporation; or

(iv)                             a merger, amalgamation, arrangement, consolidation or similar transaction following which the Company is the surviving corporation but the Common Shares outstanding immediately preceding the merger, amalgamation, arrangement, consolidation or similar transaction are converted or exchanged by virtue of the merger, amalgamation, arrangement, consolidation or similar transaction into other property, whether in the form of securities, cash or otherwise.

(l)                                    “Designated 423 Corporation” means any Related Corporation selected by the Board as participating in the 423 Component.

(m)                             “Designated Company” means any Designated Non-423 Corporation or Designated 423 Corporation, provided, however, that at any given time, a Related Corporation participating in the 423 Component shall not be a Related Corporation participating in the Non-423 Component.

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(n)                                 “Designated Non-423 Corporation” means any Related Corporation or Affiliate selected by the Board as participating in the Non-423 Component.

(o)                                 “Director” means a member of the Board.

(p)                                 “Effective Date” means the effective date of the Plan, as set forth in Section 15.

(q)                                 “Eligible Employee” means an Employee who meets the requirements set forth in the document(s) governing the Offering for eligibility to participate in the Offering, provided that such Employee also meets the requirements for eligibility to participate set forth in the Plan.

(r)                                  “Employee” means any person, including an Officer or Director, who is “employed” for purposes of Section 423(b)(4) of the Code by the Company or a Related Corporation (including an Affiliate).  However, service solely as a Director, or payment of a fee for such services, will not cause a Director to be considered an “Employee” for purposes of the Plan.

(s)                                   “Employee Stock Purchase Plan” means a plan that grants Purchase Rights intended to be options issued under an “employee stock purchase plan,” as that term is defined in Section 423(b) of the Code.

(t)                                    “Exchange Act” means the U.S. Securities Exchange Act of 1934, as amended and the rules and regulations promulgated thereunder.

(u)                                 “Fair Market Value” means, as of any date, the value of a Common Share determined as follows:

(i)                                    If the Common Shares are listed on any established stock exchange or traded on any established market, the Fair Market Value of a Common Share will be, unless otherwise determined by the Board, the closing sales price for such shares as quoted on such exchange or market (or the exchange or market with the greatest volume of trading in the Common Shares) on the date of determination, as reported in such source as the Board deems reliable.  Unless otherwise provided by the Board, if there is no closing sales price for the Common Shares on the date of determination, then the Fair Market Value will be the closing sales price on the last preceding date for which such quotation exists.

(ii)                                In the absence of such markets for the Common Shares, the Fair Market Value will be determined by the Board in good faith in compliance with applicable laws and regulations and in a manner that complies with Sections 409A of the Code.

(iii)                            Notwithstanding the foregoing, for any Offering that commences on the IPO Date, the Fair Market Value of the Common Shares on the Offering Date will be the price per share at which shares are first sold to the public in the Company’s initial public offering as specified in the final prospectus for that initial public offering.

(v)                                 “IPO Date” means the date of the underwriting agreement between the Company and the underwriter(s) managing the initial public offering of the Common Shares, pursuant to which the Common Shares are priced for the initial public offering.

(w)                               “Non-423 Component” means the part of the Plan, which excludes the 423 Component, pursuant to which Purchase Rights that are not intended to satisfy the requirements for an Employee Stock Purchase Plan may be granted to Eligible Employees.

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(x)                                 “Offering” means the grant to Eligible Employees of Purchase Rights, with the exercise of those Purchase Rights automatically occurring at the end of one or more Purchase Periods. The terms and conditions of an Offering will generally be set forth in the “Offering Document” approved by the Board for that Offering.

(y)                                 “Offering Date” means a date selected by the Board for an Offering to commence.

(z)                                  “Officer” means a person who is an officer of the Company or a Related Corporation or Affiliate within the meaning of Section 16 of the Exchange Act.

(aa)                          “Participant” means an Eligible Employee who holds an outstanding Purchase Right.

(bb)                          “Plan” means this Milestone Pharmaceuticals Inc. 2019 Employee Share Purchase Plan, including both the 423 Component and the Non-423 Component, as amended from time to time.

(cc)                            “Purchase Date” means one or more dates during an Offering selected by the Board on which Purchase Rights will be exercised and on which purchases of Common Shares will be carried out in accordance with such Offering.

(dd)                          “Purchase Period” means a period of time specified within an Offering, generally beginning on the Offering Date or on the first Trading Day following a Purchase Date, and ending on a Purchase Date.  An Offering may consist of one or more Purchase Periods.

(ee)                            “Purchase Right” means an option to purchase Common Shares granted pursuant to the Plan.

(ff)                              “Related Corporation” means any “parent corporation” or “subsidiary corporation” of the Company whether now or subsequently established, as those terms are defined in Sections 424(e) and (f), respectively, of the Code.

(gg)                          “Securities Act” means the U.S. Securities Act of 1933, as amended.

(hh)                          “Tax-Related Items” means any income tax, social insurance, payroll tax, fringe benefit tax, payment on account or other tax-related items arising in relation to a Participant’s participation in the Plan.

(ii)                                “Trading Day” means any day on which the exchange(s) or market(s) on which Common Shares are listed, including but not limited to the NYSE, Nasdaq Global Select Market, the Nasdaq Global Market, the Nasdaq Capital Market or any successors thereto, is open for trading.

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Exhibit 5.1

May 9, 2019

Milestone Pharmaceuticals Inc.

1111 Dr. Frederik-Philips Boulevard, Suite 420

Montreal, Québec

H4M 2X6

Dear Sirs/Mesdames:

Re: Milestone Pharmaceuticals Inc. - Registration Statement on Form S-8

We have acted as Canadian counsel to Milestone Pharmaceuticals Inc. (the “Corporation”), a corporation governed by the Business Corporations Act (Québec), in connection with the registration of up to 4,989,328 common shares of the Corporation, consisting of (i) up to 2,340,993 common shares of the Corporation (the “2011 Shares”) issuable pursuant to the Corporation’s 2011 stock option plan (the “2011 Plan”), (ii) up to 2,369,571 common shares of the Corporation (the “2019 Shares”) issuable pursuant to the Corporation’s 2019 equity incentive plan (the “2019 Plan”), and (iii) up to 278,764 common shares of the Corporation (the “ESPP Shares” and, collectively with the 2011 Shares and the 2019 Shares, the “Shares”) issuable pursuant to the Corporation’s 2019 employee share purchase plan (the “ESPP” and, collectively with the 2011 Plan and the 2019 Plan, the “Plans”), pursuant to a Registration Statement on Form S-8 (the “Registration Statement”) filed on May 9, 2019 with the Securities and Exchange Commission under the Securities Act of 1933, as amended, relating to the registration of the Shares.

We have examined the Registration Statement, the Plans and all such corporate and public records, statutes and regulations and have made such investigations and have reviewed such other documents as we have deemed relevant and necessary and have considered such questions of law as we have considered relevant and necessary in order to give the opinion hereinafter set forth. As to various questions of fact material to such opinions which were not independently established, we have relied upon a certificate of an officer of the Corporation.

In reviewing the foregoing documents and in giving this opinion, we have assumed the legal capacity of all individuals, the genuineness of all signatures, the veracity of the information contained therein, the authenticity of all documents submitted to us as originals and the conformity to authentic or original documents of all documents submitted to us as certified, conformed, electronic, photostatic or facsimile copies.

We are qualified to practice law in the Province of Québec and this opinion is rendered solely with respect to the Province of Québec and the federal laws of Canada applicable in the Province of Québec.

On the basis of the foregoing, we are of the opinion that, when the Shares shall have been issued and sold pursuant to the terms of the Plans and the Registration Statement, the Shares will be validly issued, fully paid and non-assessable.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement.

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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We hereby consent to the incorporation by reference in this Registration Statement on Form S-8 of Milestone Pharmaceuticals Inc. of our report dated February 18, 2019, except for the effects of the reverse share split described in Note 1, as to which the date is April 29, 2019, relating to the consolidated financial statements, which appears in Milestone Pharmaceuticals Inc.’s Registration Statement on Form S-1, as amended (No. 333-230846).

/s/PricewaterhouseCoopers LLP(1)

Montreal, Québec, Canada

May 9, 2019

(1) CPA auditor, CA, public accountancy permit No. A113048

PricewaterhouseCoopers LLP/s.r.l./s.e.n.c.r.l.

1250 René-Lévesque Boulevard West, Suite 2500, Montréal, Quebec, Canada H3B 4Y1

T: +1 514 205 5000, F: +1 514 876 1502, www.pwc.com/ca

“PwC” refers to PricewaterhouseCoopers LLP/s.r.l./s.e.n.c.r.l., an Ontario limited liability partnership.