April 25, 2018

You are cordially invited to attend the 2018 Annual Meeting of Stockholders of Aldeyra Therapeutics, Inc. that will be held on Thursday, June 7, 2018 at 10:00 a.m. local time, at the offices of Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP, One Marina Park Drive, Suite 900, Boston, MA 02210.

Details regarding admission to the Annual Meeting and the business to be conducted are described in the accompanying proxy materials. Also included is a copy of our annual report on Form 10-K for the year ended December 31, 2017. We encourage you to read this information carefully.

Your vote is important. Whether or not you plan to attend the Annual Meeting, we hope you will vote as soon as possible. You may vote over the Internet, by telephone or by mailing a proxy card, if you have requested one. Voting over the Internet, by telephone or by written proxy will ensure your representation at the Annual Meeting regardless of whether or not you attend in person. Please review the instructions on the Notice of Internet Availability of Proxy Materials you received in the mail regarding each of these voting options.

Thank you for your ongoing support of Aldeyra.

Very truly yours,

Todd C. Brady, M.D., Ph.D.

Chief Executive Officer, President and Director

ALDEYRA THERAPEUTICS, INC.

131 Hartwell Avenue, Suite 320

Lexington, Massachusetts 02421

NOTICE OF ANNUAL MEETING

FOR 2018 ANNUAL MEETING OF STOCKHOLDERS

A Notice of Internet Availability of Proxy Materials (Notice) has been mailed to stockholders of record on or about April 25, 2018. The Notice contains instructions on how to access our proxy statement for our 2018 Annual Meeting of Stockholders and our annual report on Form 10-K for the year ended December 31, 2017 (together, the proxy materials). The Notice also provides instructions on how to vote online, by telephone or by mail and includes instructions on how to receive a paper copy of proxy materials by mail. The proxy materials can be accessed directly at the following Internet address: www.proxyvote.com.

If you have any questions regarding this information or the proxy materials, please visit our website at www.aldeyra.com or contact Stephen J. Tulipano, our Chief Financial Officer, at (781) 761-4904, ext. 205.

All stockholders are cordially invited to attend the annual meeting in person.

By order of the Board of Directors,

Todd C. Brady, M.D., Ph.D.

Chief Executive Officer, President and Director

This notice of annual meeting, proxy statement and accompanying form of proxy card are being made available on or about April 25, 2018.

TABLE OF CONTENTS

ALDEYRA THERAPEUTICS, INC.

131 Hartwell Avenue, Suite 320

Lexington, Massachusetts 02421

PROXY STATEMENT FOR 2018 ANNUAL MEETING OF STOCKHOLDERS

This proxy statement is furnished in connection with solicitation of proxies by our Board of Directors for use at the 2018 Annual Meeting of Stockholders (the Annual Meeting) to be held at 10:00 a.m. local time on Thursday, June 7, 2018, and any postponements or adjournments thereof. The Annual Meeting will be held at the offices of Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP, One Marina Park Drive, Suite 900, Boston, MA 02210. Beginning on or about April 25, 2018, we mailed to our stockholders a Notice of Internet Availability of Proxy Materials (the Notice) containing instructions on how to access our proxy materials. As used in this proxy statement, the terms “Aldeyra,” the “Company,” “we,” “us,” and “our” mean Aldeyra Therapeutics, Inc. unless the context indicates otherwise.

QUESTIONS AND ANSWERS ABOUT PROCEDURAL MATTERS

Annual Meeting

You can find directions on how to instruct us to send future proxy materials to you by email at www.proxyvote.com. Choosing to receive future proxy materials by email will save us the cost of printing and mailing documents to you and will reduce the impact of our annual meetings on the environment. If you choose to receive future proxy materials by email, you will receive an email message next year with instructions containing a link to those materials and a link to the proxy voting website. Your election to receive proxy materials by email will remain in effect until you terminate it.

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Stock Ownership

Beneficial owners — Many Aldeyra stockholders hold their shares through a broker, trustee or other nominee, rather than directly in their own name. If your shares are held in a brokerage account or by a bank or another nominee (commonly referred to as being held in “street name”), you are considered the “beneficial owner” of such shares. The Notice was forwarded to you by your broker, trustee or nominee who is considered, with respect to those shares, the stockholder of record.

As the beneficial owner, you have the right to direct your broker, trustee or nominee on how to vote your shares. Beneficial owners are also invited to attend the Annual Meeting. However, since beneficial owners are not stockholders of record, you may not vote your shares in person at the Annual Meeting unless you follow your broker’s procedures for obtaining a legal proxy. If you request a printed copy of the proxy materials by mail, your broker or nominee will provide a voting instruction card for you to use.

Quorum and Voting

A proxy submitted by a stockholder may indicate that the shares represented by the proxy are not being voted with respect to a particular matter.

Under the General Corporation Law of the State of Delaware, abstentions and broker “non-votes” are counted as present and entitled to vote and are, therefore, included for purposes of determining whether a quorum is present at the Annual Meeting.

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A broker non-vote occurs when a nominee holding shares for a beneficial owner does not vote on a particular proposal because the nominee does not have discretionary voting power with respect to that item and has not received instructions from the beneficial owner.

Beneficial owners — If you are a beneficial owner holding shares through a bank, broker or other nominee, please refer to your Notice or other information forwarded by your bank or broker to see which voting options are available to you.

then the persons named as proxy holders will vote your shares in the manner recommended by our Board of Directors on all matters presented in this proxy statement and as the proxy holders may determine in their discretion with respect to any other matters properly presented for a vote at the Annual Meeting.

Beneficial owners — If you are a beneficial owner of shares held in street name and do not provide the organization that holds your shares with specific voting instructions then, under applicable rules, the

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organization that holds your shares may generally vote on “routine” matters but cannot vote on “non-routine” matters. If the organization that holds your shares does not receive instructions from you on how to vote your shares on a non-routine matter, that organization will inform the inspector of election that it does not have the authority to vote on this matter with respect to your shares. This is generally referred to as a “broker non-vote.”

Plurality means that the nominees for director receiving the greatest number of votes will be elected. Withheld votes and “broker non-votes” will have no effect on the election of a nominee.

Majority means that a proposal that receives an affirmative vote from the holders of a majority of the outstanding shares of common stock present in person or represented by proxy at the Annual Meeting. Abstentions and broker non-votes will have the same effect as an “Against” vote on this proposal.

Broker Discretionary Voting occurs when a broker does not receive voting instructions from the beneficial owner and votes those shares in its discretion on any proposal on which it is permitted to vote.

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If you are a stockholder of record, you may change your vote by (1) filing with our Corporate Secretary, prior to your shares being voted at the Annual Meeting, a written notice of revocation or a duly executed proxy card, in either case dated later than the prior proxy card relating to the same shares, or (2) by attending the Annual Meeting and voting in person (although attendance at the Annual Meeting will not, by itself, revoke a proxy). A stockholder of record that has voted on the Internet or by telephone may also change his or her vote by later making a timely and valid Internet or telephone vote.

If you are a beneficial owner of shares held in street name, you may change your vote (1) by submitting new voting instructions to your broker, trustee or other nominee or (2) if you have obtained a legal proxy from the broker, trustee or other nominee that holds your shares giving you the right to vote the shares, by attending the Annual Meeting and voting in person.

Any written notice of revocation or subsequent proxy card must be received by our Corporate Secretary prior to the taking of the vote at the Annual Meeting. Such written notice of revocation or subsequent proxy card should be hand delivered to our Corporate Secretary or should be sent so as to be delivered to our principal executive offices, Attention: Corporate Secretary.

Stockholder Proposals and Director Nominations

Requirements for stockholder proposals to be considered for inclusion in our proxy materials — Stockholders may present proper proposals for inclusion in our proxy statement and for consideration at our

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next annual meeting of stockholders by submitting their proposals in writing to our Corporate Secretary in a timely manner. In order to be included in the proxy statement for the 2019 annual meeting of stockholders, stockholder proposals must be received by our Corporate Secretary no later than December 26, 2018, and must otherwise comply with the requirements of Rule 14a-8 of the Securities Exchange Act of 1934, as amended (the Exchange Act).

Requirements for stockholder proposals to be brought before an annual meeting — In addition, our bylaws establish an advance notice procedure for stockholders who wish to present certain matters before an annual meeting of stockholders. In general, nominations for the election of directors may be made by our Board of Directors or any committee thereof or any stockholder, who is a stockholder of record on the date of the giving of such notice and on the record date for the determination of stockholders entitled to vote at such meeting, who is entitled to vote at such meeting and who has delivered written notice to our Corporate Secretary no later than the Notice Deadline (as defined below), which notice must contain specified information concerning the nominees and concerning the stockholder proposing such nominations.

Our bylaws also provide that the only business that may be conducted at an annual meeting is business that is (1) specified in the notice of meeting (or any supplement thereto) given by or at the direction of our Board of Directors, (2) otherwise properly brought before the meeting by or at the direction of our Board of Directors (or any committee thereto) or (3) properly brought before the meeting by a stockholder who has delivered written notice to our Corporate Secretary no later than the Notice Deadline (as defined below).

The “Notice Deadline” is defined as that date which is not less than 90 days nor more than 120 days prior to the one year anniversary of the previous year’s annual meeting of stockholders. As a result, the Notice Deadline for the 2019 annual meeting of stockholders is between February 7, 2019 and March 9, 2019.

If a stockholder who has notified us of his or her intention to present a proposal at an annual meeting does not appear to present his or her proposal at such meeting, we need not present the proposal for vote at such meeting.

Recommendation of director candidates — You may recommend candidates to our Board of Directors for consideration by our nominating/corporate governance committee by following the procedures set forth below in “Corporation Governance — Stockholder Recommendations for Nominations to the Board of Directors.”

Additional Information about the Proxy Materials

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Any written requests for additional information, copies of the proxy materials and 2017 Annual Report, notices of stockholder proposals, recommendations for candidates to our Board of Directors, communications to our Board of Directors or any other communications should be sent to the address above.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE STOCKHOLDER MEETING TO BE HELD ON JUNE 7, 2018.

The proxy statement and the 2017 Annual Report are available on-line at www.proxyvote.com.

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PROPOSAL 1

ELECTION OF DIRECTORS

General

Our Board of Directors may establish the authorized number of directors from time to time by resolution. Our Board of Directors is currently comprised of seven members who are divided into three classes with staggered three-year terms. A director serves in office until his respective successor is duly elected and qualified or until his earlier death or resignation. This classification of the Board of Directors into three classes with staggered three-year terms may have the effect of delaying or preventing changes in our control or management. Your proxy cannot be voted for a greater number of persons than the number of nominees named in this proxy statement.

Nominees for Election as Class I Directors at the Annual Meeting

This year’s nominees for election to the Board of Directors as our Class I directors to serve for a term of three years expiring at the 2021 annual meeting of stockholders, or until their successors have been duly elected and qualified or until their earlier death, resignation or removal, are provided below. All of the nominees listed below are currently directors of the Company. The age of each director as of April 13, 2018 is set forth below. Each of the nominees has agreed to serve as a director if elected, and we have no reason to believe that any nominee will be unable to serve if elected.

The following is additional information about each of the nominees as of the date of this proxy statement, including their business experience, public company director positions held currently or at any time during the last five years, involvement in certain legal or administrative proceedings, if applicable, and the experiences, qualifications, attributes or skills that caused the nominating/corporate governance committee and our Board of Directors to determine that the nominees should serve as one of our directors.

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Required Vote and Recommendation of the Board of Directors for Proposal 1

The affirmative vote of a plurality of the votes cast at the Annual Meeting is required for the election of our Class I directors. The two nominees receiving the most “FOR” votes among votes properly cast in person or by proxy will be elected to the Board of Directors as Class I directors. You may vote “FOR” or “WITHHOLD” on each of the nominees for election as director. Shares represented by signed proxy cards will be voted on Proposal 1 “FOR” the election of Drs. Bronstein and Treu to the Board of Directors at the Annual Meeting, unless otherwise marked on the card. A broker non-vote or a properly executed proxy marked “WITHHOLD” with respect to the election of a Class I director will not be voted with respect to such director, although it will be counted for purposes of determining whether there is a quorum.

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE “FOR” THE CLASS I

NOMINEES NAMED ABOVE.

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Continuing Directors Not Standing for Election

Certain information about those directors whose terms do not expire at the Annual Meeting is furnished below, including their business experience, public company director positions held currently or at any time during the last five years, involvement in certain legal or administrative proceedings, if applicable, and the experiences, qualifications, attributes or skills that caused the nominating/corporate governance committee and our Board of Directors to determine that the directors should serve as one of our directors. The age of each director as of April 13, 2018 is set forth below.

Incumbent Class II Directors Whose Term Expires in 2019

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Incumbent Class III Directors Whose Term Expires in 2020

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There are no family relationships among any of our directors or executive officers. See “Corporate Governance” below for additional information regarding our Board of Directors.

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PROPOSAL 2

RATIFICATION OF THE APPOINTMENT OF

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

General

Our audit committee has appointed the firm of BDO USA, LLP, independent registered public accountants, to audit our financial statements for the year ending December 31, 2018. BDO USA, LLP has audited our financial statements since the fiscal year ended December 31, 2013.

Notwithstanding its selection and even if our stockholders ratify the selection, our audit committee, in its discretion, may appoint another independent registered public accounting firm at any time during the year if the audit committee believes that such a change would be in the best interests of Aldeyra and its stockholders. At the Annual Meeting, the stockholders are being asked to ratify the appointment of BDO USA, LLP as our independent registered public accounting firm for the year ending December 31, 2018. Our audit committee is submitting the selection of BDO USA, LLP to our stockholders because we value our stockholders’ views on our independent registered public accounting firm and as a matter of good corporate governance. Representatives of BDO USA, LLP are expected to be present at the Annual Meeting and they will have an opportunity to make statements and will be available to respond to appropriate questions from stockholders.

If this proposal does not receive the affirmative approval of a majority of the votes cast on the proposal, the audit committee would reconsider the appointment.

Principal Accounting Fees and Services

The following table sets forth all fees paid or accrued by us for professional audit services and other services rendered by BDO USA, LLP during the years ended December 31, 2017 and 2016:

Pre-Approval of Audit and Non-Audit Services

Consistent with requirements of the SEC and the Public Company Accounting Oversight Board regarding auditor independence, our audit committee is responsible for the appointment, compensation and oversight of the work of our independent registered public accounting firm. In recognition of this responsibility, our audit committee (or the chair if such approval if needed on a time urgent basis) generally pre-approves of all audit and permissible non-audit services provided by the independent registered public accounting firm. These services may include audit services, audit-related services, tax services and other services.

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE “FOR” RATIFICATION OF THE APPOINTMENT OF BDO USA, LLP AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR THE YEAR ENDING DECEMBER 31, 2018.

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PROPOSAL 3

AMENDMENT TO OUR 2013 EQUITY INCENTIVE PLAN (2013 PLAN)

General

We are asking our stockholders to approve an amendment to our 2013 Equity Incentive Plan (the “2013 Plan”) to modify the automatic “evergreen” provisions regarding the number of shares to be annually added to the 2013 Plan and, in addition, implement limitations on the value of equity that may be granted under the plan to a non-employee director during a calendar year (in aggregate, the “Amendment”). Our compensation committee approved the Amendment, subject to approval of the Board of Directors and the stockholders, and the Board of Directors approved the Amendment, subject to approval of the stockholders. If our stockholders do not approve the Amendment, the existing version of the 2013 Plan, as amended to date will remain in effect.

The Amendment provides for:

Background and Reason for the Proposal

Since 2013, our number of employees has grown consistently on an annual basis. Equity awards are used as compensation vehicles by most, if not all, of the companies with which we compete for talent, and we believe that providing equity awards is critical to attract and retain key contributors. Accordingly, our Board of Directors has approved a modification to the automatic “evergreen” provision in the 2013 Plan to increase to the share reserve under the 2013 Plan to ensure a sufficient number of shares will be available for recruiting new employees and retention of existing employees. Should stockholder approval of this Proposal 3 not be obtained, the provisions regarding the annual automatic increase of shares available under the 2013 Plan will not be amended. However, we will retain the ability to issue the shares of our Common Stock which were previously approved by stockholders for issuance under the 2013 Plan.

The 2013 Plan currently limits the grant of stock options and stock appreciation rights to employees to no more than 250,000 shares during any single fiscal year, other than to a new employee in the fiscal year in which service commences. Our Board of Directors has also determined that the maximum annual aggregate grant date fair value (as determined in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718 (Topic 718), or any successor thereto) of options and stock appreciation rights that may be granted under the 2013 Plan to a non-employee director as compensation for services as a non-employee director during a calendar year shall not exceed $500,000. In addition, the maximum aggregate grant date fair value (as determined in accordance with Topic 718, or any successor thereto) of shares of common stock issued as either restricted shares or stock units that may be granted under the 2013 Plan to a non-employee director as compensation for services as a non-employee director during a calendar year shall not exceed $500,000.

Equity Compensation Plan Information

The following table provides information as of December 31, 2017, with respect to shares of our common stock that may be issued, subject to certain vesting requirements, under our existing equity compensation plans, including our 2013 Equity Incentive Plan (2013 Plan), 2010 Employee, Director and Consultant Equity Incentive Plan (2010 Plan), our 2004 Employee, Director and Consultant Stock Plan (2004 Plan) and our 2016 Employee Stock Purchase Plan (2016 ESPP).

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Material Terms of 2013 Plan

The following is a summary of the principal features of the 2013 Plan and the Amendment. This summary does not purport to be a complete description of all of the provisions of the 2013 Plan and the Amendment. It is qualified in its entirety by reference to the full text of the 2013 Plan and the Amendment, a copy of which has been filed with the SEC with this Proxy Statement as Appendix A, and any stockholder who desires to obtain a copy of the 2013 Plan and the Amendment may do so by written request to the Company at 131 Hartwell Avenue, Suite 320, Lexington, Massachusetts 02421, Attn: Secretary.

Share Reserve. The number of shares of our common stock available for issuance under our 2013 Plan will equal 1,148,258 shares. Of these, as of April 13, 2018, 7,762 shares have been issued upon exercise of options, approximately 2,848,844 shares are subject to outstanding options (with exercise prices ranging from $4.59 to $8.60, a weighted average exercise price of $6.54 per share and expiration dates ranging from May 2024 to March 2028); 219,072 shares are subject to outstanding unvested/unsettled Restricted Stock Units (RSUs), no shares are subject to outstanding Stock Appreciation Rights (SARs) or unvested restricted/performance share awards; and approximately 912,448 shares remain available for issuance pursuant to awards to be granted under the 2013 Plan.

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If the Amendment is approved, the number of shares reserved for issuance under the 2013 Plan will be increased automatically on January 1 of each year during the term of the plan, starting with January 1, 2019, by a number equal to the smallest of:

In general, if awards under the 2013 Plan are forfeited, terminate, expire or lapse without the issuance of shares, if we repurchase shares issued under the 2013 Plan, if shares are applied to pay the exercise or purchase price of an award or are withheld to satisfy tax obligations with respect to any award, then such shares will again become available for awards. All share numbers described in this summary of the 2013 Plan will automatically adjust in the event of a stock split, a stock dividend, or a reverse stock split.

Administration. Our compensation committee administers the 2013 Plan. The committee has complete discretion to make all decisions relating to the 2013 Plan and outstanding awards, including repricing outstanding options and modifying outstanding awards. Our compensation committee has established a Stock Option Committee whose purpose is to approve stock option grants to our employees subject to guidelines previously approved by our compensation committee. Our compensation committee appointed our Chief Executive Officer, Todd Brady, M.D., Ph.D., as the sole member of this committee.

Eligibility. Employees, non-employee directors and consultants are eligible to participate in our 2013 Plan. However, only non-employee directors are eligible to participate in the automatic annual option grants pursuant to our non-employee director compensation program (see “Annual Director Grant Program” below). As of April 13, 2018, approximately 20 persons (including three executive officers and six non-employee directors) were eligible to participate in the 2013 Plan.

Types of Award. Our 2013 Plan provides for the following types of awards:

Option and Stock Appreciation Rights. The exercise price for options granted under the 2013 Plan may not be less than 100% of the fair market value of our common stock on the grant date. Optionees may pay the exercise price in cash or, with the consent of the compensation committee and as set forth in the applicable agreement:

A participant who exercises a stock appreciation right receives the increase in value of our common stock over the base price. The base price for stock appreciation rights may not be less than 100% of the fair market value of our common stock on the grant date. The settlement value of a stock appreciation right may be paid in cash or shares of common stock or a combination of both.

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Options and stock appreciation rights vest at the time or times determined by the compensation committee. In most cases, they will vest over a four-year period following the date of grant. Options and stock appreciation rights also expire at the time determined by the compensation committee but in no event more than 10 years after they are granted. These awards generally expire earlier if the participant’s service terminates earlier. No participant may be granted stock options and stock appreciation rights covering more than 250,000 shares during any single fiscal year, other than to a new employee in the fiscal year in which service commences. In addition, the maximum annual aggregate grant date fair value (as determined in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718 (Topic 718), or any successor thereto) of options and stock appreciation rights that may be granted under the 2013 Plan to a non-employee director as compensation for services as an non-employee director during a calendar year shall not exceed $500,000.

Restricted Shares and Stock Units. Restricted shares and stock units may be awarded under the 2013 Plan in return for any lawful consideration (and as set forth in the applicable award agreement), and participants who receive restricted shares or stock units generally are not required to pay for their awards in cash. In general, these awards will be subject to vesting. Vesting may be based on length of service, the attainment of performance-based milestones, or a combination of both, as determined by the compensation committee. No participant may be granted awards of restricted shares and stock units covering more than 250,000 shares during any single fiscal year, other than to a new employee in the fiscal year in which service commences. In addition, the maximum aggregate grant date fair value (as determined in accordance with ASC Topic 718, or any successor thereto) of shares of common stock issued as either restricted shares or stock units that may be granted under the 2013 Plan to a non-employee director as compensation for services as an non-employee director during a calendar year shall not exceed $500,000. These annual limits are in addition to any stock options and stock appreciation rights the participant may receive during a fiscal year. Settlement of vested stock units may be made in the form of cash, shares of common stock, or a combination of both.

Performance Cash Awards. Performance cash awards may be granted under the 2013 Plan that qualify as performance-based compensation that is not subject to the income tax deductibility limitations imposed by Section 162(m) of the Code on our executive officers, if the award is approved by a committee of “outside directors’ as defined in Section 162(m) of the Code and the grant or vesting of the award is tied solely to the attainment of performance goals during a designated performance period. No participant may be paid more than $6.0 million in cash in any fiscal year pursuant to a performance cash award granted under the 2013 Plan.

Performance goals for the grant or vesting of awards under the 2013 Plan include earnings (before or after taxes); earnings per share; earnings before interest, taxes, depreciation and amortization; total stockholder return; stockholders equity or return on equity or average stockholders’ equity; return on assets, investment or capital employed; operating income; gross margin; operating margin; net operating income (before or after taxes); return on operating revenue; specified levels or changes in sales or revenue; expense or cost reduction; working capital; economic value added; market share; cash flow; operating cash flow; cash flow per share; share price; debt reduction; customer satisfaction; contract awards or backlog; or other objective corporate or individual strategic or individual performance goals. To the extent a performance award is not intended to comply with Section 162(m) of the Code, the compensation committee may select other measures of performance.

Automatic Director Grants. Under our non-employee director compensation plan, non-employee members of our Board of Directors will also receive automatic grants of non-statutory stock options under our 2013 Plan upon joining the Board of Directors and on the date of each annual meeting of stockholders. For purposes of our automatic director grant program, a non-employee director is a director who is not employed by us and who does not receive compensation from us or have a business relationship with us that would require disclosure under certain Securities and Exchange Commission rules. See the section below entitled “Corporate Governance — Director Compensation — Non-Employee Director Compensation” for more detail on our non-employee director compensation plan.

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Corporate Transactions. In the event we are a party to a merger, consolidation or a change in control transaction, outstanding awards granted under the 2013 Plan, and all shares acquired under the plan, will be subject to the terms of the definitive transaction agreement (or, if there is no such agreement, as determined by our compensation committee. Unless an award agreement provides otherwise, such treatment shall include (without limitation) any of the following with respect to each outstanding award:

The compensation committee has the discretion to provide that an award granted under the 2013 Plan will vest on an accelerated basis if a change in control of our company occurs or if the participant is subject to an involuntary termination, either at the time such award is granted or afterward.

A change in control includes:

The compensation committee is not required to treat all awards, or portions thereof, in the same manner.

For information regarding the vesting acceleration provisions applicable to the equity awards held by our named executive officers under our Change in Control Plan, please see “Severance and Change in Control Benefits” below.

Changes in Capitalization. In the event that there is a change in the capital structure of our common stock, such as a stock split, reverse stock split, or dividend paid in common stock, proportionate adjustments will automatically be made to the kind and maximum number of shares:

In the event that there is a declaration of an extraordinary dividend payable in a form other than our common stock in an amount that has a material effect on the price of our common stock, a recapitalization, a spin-off or a similar occurrence, the compensation committee may make such adjustments as it deems appropriate, in its sole discretion, to one or more of the foregoing.

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Amendments or Termination. Our Board of Directors may amend or terminate the 2013 Plan at any time and for any or no reason. If our board of directors amends the 2013 Plan, it does not need to ask for stockholder approval of the amendment unless required by applicable law or exchange listing requirements. The 2013 Plan will continue in effect for 10 years, unless our Board of Directors decides to terminate the plan earlier or unless our Board of Directors and stockholders later approve an extension of this term.

New Plan Benefits and Option Grant Table

Because the 2013 Plan is discretionary, benefits to be received by individual participants are not determinable, other than the grants currently provided for under our non-employee director compensation plan. See the section below entitled “Corporate Governance — Director Compensation — Non-Employee Director Compensation” for more detail on our non-employee director compensation plan. The table below shows, as to each of our current executive officers and the various indicated groups (a) the number of shares of Common Stock for which options have been granted for (i) the one (1)-year period ended December 31, 2017 and (ii) the period from January 1, 2018 through April 13, 2018 and (b) the weighted-average exercise price per share. No shares of stock were directly issued to the individuals or groups below during the one (1)-year period ended December 31, 2016 or the period through April 13, 2018.

In addition, during (i) the one (1)-year period ended December 31, 2017, Dr. Brady was awarded an RSU covering 136,806 shares of Common Stock and (ii) the period from January 1, 2018 through April 13, 2018, Dr. Brady was awarded an RSU covering 96,144 shares of Common Stock.

Federal Income Tax Consequences of Options Granted under the 2013 Plan. The following is intended only as a general guide as to the United States federal income tax consequences under current law for the 2013 Plan and does not attempt to describe all possible federal or other tax consequences of such participation or tax consequences based on particular circumstances. Options granted under the 2013 Plan may be either incentive stock options that satisfy the requirements of Section 422 of the Code or non-statutory options that are not intended to meet such requirements. The federal income tax treatment for the two types of options differs, as follows:

Incentive Stock Options. No taxable income is recognized by the optionee at the time of the option grant, and no taxable income is generally recognized at the time the option is exercised. However, the excess of the fair market value of the purchased shares on the exercise date over the exercise price paid for the shares generally is includable in alternative minimum taxable income. The optionee will recognize taxable income in the year in which the purchased shares are sold or otherwise made the subject of disposition.

For federal tax purposes, dispositions are divided into two categories: (i) qualifying and (ii) disqualifying. The optionee will make a qualifying disposition of the purchased shares if the sale or other disposition of such shares is made after the optionee has held the shares for more than two (2) years after the grant date of the option and more than one (1) year after the exercise date. If the optionee fails to satisfy either of these two holding periods prior to the sale or other disposition of the purchased shares, then a disqualifying disposition will result.

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Upon a qualifying disposition of the shares, the optionee will recognize long-term capital gain in an amount equal to the excess of (i) the amount realized upon the sale or other disposition of the purchased shares over (ii) the exercise price paid for such shares. If there is a disqualifying disposition of the shares, then the optionee will realize taxable ordinary income equal to the lesser of (a) the excess of (i) the fair market value of those shares on the date the option was exercised (or if later the date any forfeiture restriction lapsed) over (ii) the exercise price paid for the shares, or (b) the optionee’s actual gain, if any, on the purchase and sale. Any additional gain recognized upon the disposition will be a capital gain.

If the optionee makes a disqualifying disposition of the purchased shares, then the Company will be entitled to an income tax deduction for the taxable year in which such disposition occurs equal to the excess of (i) the fair market value of such shares on the date the option was exercised (or if later the date any forfeiture restriction lapsed) over (ii) the exercise price paid for the shares. In no other instance will the Company be allowed a deduction with respect to the optionee’s disposition of the purchased shares. The Company anticipates that any compensation deemed paid by the Company upon one or more disqualifying dispositions of incentive stock option shares by the Company’s executive officers will remain deductible by the Company and will not have to be taken into account for purposes of the $1,000,000 limitation per covered individual on the deductibility of the compensation paid to certain executive officers of the Company.

Non-Statutory Options. No taxable income is recognized by an optionee upon the grant of a non-statutory option. The optionee will in general recognize ordinary income in the year in which the option is exercised equal to the excess of the fair market value of the purchased shares on the exercise date over the exercise price paid for the shares, and the optionee will be required to satisfy the tax withholding requirements applicable to such income.

Special provisions of the Code apply to the acquisition of Common Stock under a non-statutory option if the purchased shares are subject to repurchase by the Company. These special provisions may be summarized as follows:

The Company will be entitled to a business expense deduction equal to the amount of ordinary income recognized by the optionee with respect to the exercised non-statutory option. The deduction will in general be allowed for the taxable year of the Company in which such ordinary income is recognized by the optionee. The Company anticipates that the compensation deemed paid by the Company upon the exercise of non-statutory options with exercise prices equal to the fair market value of the option shares on the grant date will remain deductible by the Company and will not have to be taken into account for purposes of the $1,000,000 limitation per covered individual on the deductibility of the compensation paid to certain executive officers of the Company.

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Stock Appreciation Rights. A participant who is granted a SAR will recognize ordinary income in the year of exercise equal to the amount of the appreciation distribution. The Company will be entitled to a business expense deduction equal to the appreciation distribution for the taxable year of the Company in which the ordinary income is recognized by the participant.

Restricted Stock Issuances.    The tax principles applicable to direct restricted stock issuances under the 2013 Plan will be substantially the same as those summarized above for the exercise of non-statutory options.

Stock Units.    A participant who is granted a stock unit will recognize ordinary income in the year in which the shares subject to the award are actually issued to the participant in an amount equal to the fair market value of the shares on the date of issuance. The Company will be entitled to a business expense deduction equal to the amount of ordinary income recognized by the participant at the time the shares are issued for the taxable year in which such ordinary income is recognized by the participant.

Required Vote and Recommendation of the Board of Directors for Proposal 3

The affirmative vote from the holders of a majority of the outstanding shares of common stock present in person or represented by proxy at the Annual Meeting is required to approve the Amendment. Abstentions and broker non-votes will have the same effect as an “Against” vote on this proposal.

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS A VOTE “FOR” APPROVAL OF THE AMENDMENTS TO THE 2013 PLAN.

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CORPORATE GOVERNANCE

Code of Conduct

Our Board of Directors adopted a code of business conduct that applies to each of our directors, officers and employees. The full text of our code of business conduct is posted on the Investors portion of our website at http://ir.aldeyra.com. Any waiver of the code of business conduct for an executive officer or director may be granted only by our Board of Directors or a committee thereof and must be timely disclosed as required by applicable law. We have implemented whistleblower procedures that establish format protocols for receiving and handling complaints from employees. Any concerns regarding accounting or auditing matters reported under these procedures will be communicated promptly to the audit committee.

Board Composition

Our business affairs are managed under the direction of our Board of Directors, which is currently composed of seven members. All of our directors, other than Dr. Brady, are independent within the meaning of the listing rules of The Nasdaq Stock Market (Nasdaq). Our Board of Directors is divided into three classes with staggered three-year terms. At each annual meeting of stockholders, the successors to directors whose terms then expire will be elected to serve from the time of election and qualification until the third annual meeting following election.

Directors in a particular class will be elected for three-year terms at the annual meeting of stockholders in the year in which their terms expire. As a result, only one class of directors will be elected at each annual meeting of our stockholders, with the other classes continuing for the remainder of their respective three-year terms. Each director’s term continues until the election and qualification of his or her successor, or the earlier of his or her death, resignation or removal. The classification of our Board of Directors may have the effect of delaying or preventing changes in our control or management.

Director Independence

Our common stock is listed on The Nasdaq Capital Market. The listing rules of this stock exchange generally require that a majority of the members of a listed company’s Board of Directors be independent. In addition, the rules of the Nasdaq require that, subject to specified exceptions, each member of a listed company’s audit, compensation, and nominating/corporate governance committees be independent. The Nasdaq director independence definition includes a series of objective tests, such as that the director is not also one of our employees and has not engaged in various types of business dealings with us. In addition, as further required by the Nasdaq rules, our Board of Directors has made a subjective determination as to each independent director that no relationships exist which, in the opinion of our Board of Directors, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In making these determinations, our directors reviewed and discussed information provided by the directors and us with regard to each director’s business and personal activities as they may relate to us and our management.

Our Board of Directors has determined that none of our non-employee directors has a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director and that each of these directors is “independent” as that term is defined under the rules of the Nasdaq. The independent members of our Board of Directors will hold separate regularly scheduled executive session meetings at which only independent directors are present.

Audit committee members must also satisfy the independence criteria set forth in Rule 10A-3 under the Exchange Act. In order to be considered independent for purposes of Rule 10A-3, a member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee, the Board of Directors, or any other board committee: accept, directly or indirectly, any consulting, advisory, or

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other compensatory fee from the listed company or any of its subsidiaries; or be an affiliated person of the listed company or any of its subsidiaries. Each of Martin J. Joyce, Ben R. Bronstein, M.D. and Jesse I. Treu, Ph.D. qualify as an independent director pursuant to Rule 10A-3.

Board Leadership Structure

Our Board of Directors is currently led by its chairman, Dr. Douglas. Our Board of Directors recognizes that it is important to determine an optimal board leadership structure to ensure the independent oversight of management as the company continues to grow. We separate the roles of chief executive officer and chairman of the Board of Directors in recognition of the differences between the two roles. The chief executive officer is responsible for setting the strategic direction for the company and the day-to-day leadership and performance of the company, while the chairman of the Board of Directors presides over meetings of the full Board of Directors. We believe that this separation of responsibilities provides a balanced approach to managing the Board of Directors and overseeing the company.

Our Board of Directors has concluded that our current leadership structure is appropriate at this time. However, our Board of Directors will continue to periodically review our leadership structure and may make such changes in the future as it deems appropriate.

Board Committees

Our Board of Directors has established an audit committee, a compensation committee, a nominating/corporate governance committee and a stock option committee. The composition of these committees meets the criteria for independence under, and the functioning of these committees comply with the applicable requirements of the Sarbanes-Oxley Act of 2002, the current rules of The Nasdaq Capital Market and SEC rules and regulations. We intend to comply with future requirements as they become applicable to us. Each committee has the composition and responsibilities described below.

Audit Committee

During our year ended December 31, 2017, our audit committee held 4 meetings. The members of our audit committee are Martin J. Joyce, Ben R. Bronstein, M.D. and Jesse I. Treu, Ph.D., each of whom is a non-employee member of the Board of Directors. Mr. Joyce serves as the chair of the audit committee.

The audit committee’s main function is to oversee our accounting and financial reporting processes, internal systems of control, independent registered public accounting firm relationships and the audits of our financial statements. Pursuant to the audit committee charter, the functions of the committee include, among other things:

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All members of our audit committee meet the requirements for financial literacy under the applicable rules and regulations of the SEC and The Nasdaq Capital Market. Our Board of Directors has determined that Mr. Joyce is an “audit committee financial expert” as defined by applicable SEC rules and has the requisite financial sophistication as defined under the applicable Nasdaq rules and regulations.

Compensation Committee

During our year ended December 31, 2017, our compensation committee held 1 meeting and acted by written consent 2 times. The members of our compensation committee are Ben R. Bronstein, M.D., Neal S. Walker, D.O. and Gary Phillips, M.D. Dr. Phillips serves as the chair of the compensation committee. Our compensation committee reviews and recommends policies relating to compensation and benefits of our officers and employees.

Pursuant to the compensation committee charter, the functions of this committee include:

Our Board of Directors has determined that each of Ben R. Bronstein, M.D., Neal S. Walker, D.O. and Gary Phillips, M.D. is independent under the applicable rules and regulations of Nasdaq, is a “non-employee director” as defined in Rule 16b-3 promulgated under the Exchange Act.

Our chief executive officer and chief financial officer assist our compensation committee in carrying out its functions, although they do not participate in deliberations or decisions with respect to their own compensation. Since January 2015, our compensation committee has engaged the services of Pearl Meyer& Partners, LLC (Pearl Meyer), a compensation consulting firm, to advise the compensation committee regarding the amount and types of compensation that we provide to our executives and directors and how our compensation practices compared to the compensation practices of other companies. Pearl Meyer reports directly to the compensation committee. Pearl Meyer does not provide any services to us other than the services provided to the compensation committee. The compensation committee believes that Pearl Meyer does not have any conflicts of interest in advising the compensation committee under applicable SEC rules or Nasdaq listing standards.

Nominating/Corporate Governance Committee

During our year ended December 31, 2017, our nominating/corporate governance committee held 3 meetings. The members of our nominating/corporate governance committee are Martin J. Joyce, Jesse Treu,

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Ph.D. and Richard H. Douglas, Ph.D. Pursuant to the nominating/corporate governance committee charter, the functions of this committee include, among other things:

Stock Option Committee

During our year ended December 31, 2017, our stock option committee did not hold any meetings and acted by written consent 3 times. The sole member of our stock option committee is Todd C. Brady, M.D., Ph.D. Pursuant to the stock option committee charter, the function of this committee includes, among other things, granting stock options to non-executive employees under our 2013 Equity Incentive Plan within certain grant guidelines specified in the stock option committee charter or as adopted from time to time by our Board of Directors or compensation committee.

Compensation Committee Interlocks and Insider Participation

None of the members of our compensation committee is or has in the past 5 years served as an officer or employee of our company. None of our executive officers currently serves, or in the past year has served, as a member of the Board of Directors or compensation committee of any entity that has one or more executive officers serving on our Board of Directors or compensation committee.

Meetings of the Board of Directors

The full Board of Directors held 8 meetings during our year ended December 31, 2017. No director attended fewer than 75% of the total number of meetings of the Board of Directors and of any committees of the Board of Directors of which he was a member during our year ended December 31, 2017.

It is our policy that directors are invited and encouraged to attend our annual meetings of stockholders. We expect to schedule our annual meetings on the same day as a regularly scheduled Board of Directors meeting in order to facilitate attendance by the members of our Board of Directors. One of our then-serving directors attended our 2017 annual meeting of stockholders.

Stockholder Recommendations for Nominations to the Board of Directors

Our nominating/corporate governance committee will consider director candidates recommended by stockholders and evaluate them using the same criteria as candidates identified by the Board of directors or the nominating/corporate governance committee for consideration. If a stockholder of the Company wishes to recommend a director candidate for consideration by the nominating/corporate governance committee, the stockholder recommendation should be delivered to the Corporate Secretary of the Company at the principal executive offices of the Company, and must include information regarding the candidate and the stockholder making the recommendation as required by our Bylaws.

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Board Oversight of Risk

Our Board of Directors has responsibility for the oversight of the company’s risk management processes and, either as a whole or through its committees, regularly discusses with management our major risk exposures, their potential impact on our business and the steps we take to manage them. The risk oversight process includes receiving regular reports from board committees and members of senior management to enable our Board of Directors to understand the company’s risk identification, risk management and risk mitigation strategies with respect to areas of potential material risk, including operations, finance, legal, regulatory, strategic and reputational risk.

The audit committee reviews information regarding liquidity and operations, and oversees our management of financial risks. Periodically, the audit committee reviews our policies with respect to risk assessment, risk management, loss prevention and regulatory compliance. Oversight by the audit committee includes direct communication with our external auditors, and discussions with management regarding significant risk exposures and the actions management has taken to limit, monitor or control such exposures. The compensation committee is responsible for assessing whether any of our compensation policies or programs has the potential to encourage excessive risk-taking. The nominating/corporate governance committee manages risks associated with the independence of the Board of Directors, corporate disclosure practices, and potential conflicts of interest. While each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire board is regularly informed through committee reports about such risks. Matters of significant strategic risk are considered by our Board of Directors as a whole.

Director Compensation

The following table sets forth information about the compensation of the non-employee members of our Board of Directors who served as a director during our year ended December 31, 2017. Other than as set forth in the table and described more fully below, during our year ended December 31, 2017, we did not pay any fees to, make any equity awards or non-equity awards to or pay any other compensation to the non-employee members of our Board of Directors. Dr. Brady, our chief executive officer, receives no compensation for his service as a director, and is not included in the table below. Mr. Douglas currently serves as chair of our Board of Directors.

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Non-Employee Director Compensation

For the year ended December 31, 2017, pursuant to our then current non-employee director compensation plan, each non-employee member of our Board of Directors received the following cash and equity compensation for board services, as applicable:

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In addition, the following rules apply to initial and annual equity awards:

For purposes of our non-employee director compensation plans or programs, a non-employee director is a director who is not employed by us and who does not receive compensation from us or have a business relationship with us that would require disclosure under certain rules of the SEC.

We also reimburse our non-employee directors for their reasonable out-of-pocket expenses incurred in attending Board of Directors and committee meetings.

“Change in Control” means the occurrence of any of the following: (a) any “person” (as such term is used in Sections 13(d) and 14(d) of the Exchange Act) becomes the “beneficial owner” (as defined in Rule 13d-3 of the Exchange Act), directly or indirectly, of our securities representing more than fifty percent (50%) of the total voting power represented by our then-outstanding voting securities; (b) the consummation of the sale or disposition by us of all or substantially all of our assets; (c) the consummation of a merger or consolidation of our company with or into any other entity, other than a merger or consolidation which would result in the voting securities of our company outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity or its parent) more than fifty percent (50%) of the total voting power represented by the voting securities of our company or such surviving entity or its parent outstanding immediately after such merger or consolidation; or (d) individuals who are members of our Board of Directors (the Incumbent Board) cease for any reason to constitute a majority of the members of our Board of Directors over a period of 12 months; provided, however, that if the appointment or election (or nomination for election) of any new member of our Board of Directors was approved or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member shall, for purposes hereof, be considered as a member of the Incumbent Board. A transaction shall not constitute a Change in Control under the definition set forth in the preceding sentence if its sole purpose is to change the state of our incorporation or to create a holding company that will be owned in substantially the same proportions by the persons who held our securities immediately before such transaction. In addition, if a Change in Control constitutes a payment event with respect to any equity or other benefit that provides for a deferral of compensation and which is subject to Section 409A of the Internal Revenue Code of 1986, as amended (the Code), then notwithstanding anything to the contrary in this letter agreement or in any document governing such

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award, the transaction with respect to such equity or other benefit must also constitute a “change in control event” as defined in Treasury Regulation Section 1.409A-3(i)(5) to the extent required by Section 409A of the Code.

Stockholder Communications with the Board of Directors

Stockholders wishing to communicate with the Board of Directors or with an individual member of the Board of Directors may do so by writing to the Board of Directors or to the particular member of the Board of Directors, care of the Corporate Secretary by mail to our principal executive offices, Attention: Corporate Secretary. The envelope should indicate that it contains a stockholder communication. All such stockholder communications will be forwarded to the director or directors to whom the communications are addressed.

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EXECUTIVE OFFICERS

The following table provides information concerning our executive officers as of April 13, 2018:

Todd C. Brady, M.D., Ph.D. See biographical information set forth above under “Proposal 1 — Election of Directors — Incumbent Class III Directors Whose Term Expires in 2020.”

Stephen Tulipano has served as our Chief Financial Officer since June 2014. He has over 30 years of accounting and financial experience, of which 18 years were focused on the pharmaceutical industry. Most recently, he held positions at Three Tulips Inc., an accounting and management advisory services firm, where he provided full-time accounting services and financial management counsel from September 2010 to June 2014. Prior to that, from April 2006 to July 2010, he served as Chief Financial Officer, Treasurer and Secretary of Javelin Pharmaceuticals where he helped lead the company through its acquisition by Hospira in 2010. Previously, he held the role of Director of Corporate Accounting at Biogen Idec. He has also held several accounting roles both within companies and accounting firms. Mr. Tulipano holds a B.S. in Business Administration and Accounting from Salem State College and an M.B.A. in Finance from the Sawyer School of Management at Suffolk University. He is also a Certified Public Accountant.

David J. Clark, M.D. has served as our Chief Medical Officer since January 2016. He has approximately 19 years of global industry experience in both pharmaceutical firms and biotechnology companies based in the United States and Europe. Prior to joining Aldeyra, Dr. Clark served as the Chief Medical Officer of Wilson Therapeutics, a privately-held biotechnology company developing novel pharmaceuticals to treat Wilson Disease, a rare autosomal recessive disorder of copper metabolism, from 2013 to 2015. Prior to that, from September 2011 to February 2013, he served as the Senior Vice President of Translational Medicine of TransTech Pharma, LLC, a privately held pharmaceutical company focused on the discovery and development of human therapeutics across a wide range of indications in several therapeutic areas, including metabolic, neuroscience, respiratory, ophthalmology and oncology. Previously, he held the role of Chief Medical Officer at NormOxys Inc., a privately held biotechnology company focused on the development of a new class of small molecule drugs for the treatment of oncology, cardiovascular and neuroscience indications. Dr. Clark has also held clinical leadership positions at Pfizer Inc. from 2001 to 2009 and at GlaxoSmithKline plc from 1997 to 2001. Dr. Clark received his medical degree from the University of Edinburgh, trained in internal medicine and conducted respiratory medicine academic research in the UK before moving into pharmaceutical industry research.

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EXECUTIVE COMPENSATION

Summary Compensation Table

The following table provides information concerning the compensation paid to our Chief Executive Officer, our next two most highly compensated executive officers for our year ended December 31, 2017. We refer to these individuals as our named executive officers.

Narrative Explanation of Certain Aspects of the Summary Compensation Table

Employment Letters

In November 2013, we entered into a letter agreement with Dr. Brady that became effective upon our initial public offering in May 2014. We and Dr. Brady amended such letter agreement in February 2014. Dr. Brady’s base salary for 2018 is $506,000 and his target bonus is $253,000.

In June 2014, we entered into a letter agreement with Mr. Tulipano in connection with the commencement of his employment. Mr. Tulipano’s base salary for 2018 is $356,296 and his target bonus is $124,704.

In December 2015, we entered into a letter agreement with Dr. Clark in connection with the commencement of his employment. Dr. Clark’s base salary for 2018 is $424,445 and his target bonus is $148,556.

Except as described below under “Severance and Change in Control Benefits,” each of our named executive officers must remain employed with us through the date of payment to be eligible to receive a bonus.

Each of our named executive officers is eligible to receive certain benefits in the event of a change in control or if his employment is terminated under certain circumstances, as described under “Severance and Change in Control Benefits” below.

Equity Compensation

We offer stock options, restricted shares and restricted stock units to our named executive officers as the long-term incentive component of our compensation program. We typically grant equity awards to new hires upon their commencing employment with us and provide additional grants annually.

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In March 2017, Drs. Brady and Clark and Mr. Tulipano were each granted an option to purchase shares of common stock. The table below provides details regarding the foregoing grants.

In March 2017, Dr. Brady was granted a restricted stock unit award for 136,806 shares of common stock. The restricted stock unit vests in equal annual installments over four years of service following March 3, 2017 provided Dr. Brady provides continuous service to us through each such vesting date.

As discussed below under “Severance and Change in Control Benefits,” stock options granted to our named executive officers are generally subject to accelerated vesting in the event such officer is subject to an involuntary termination or if we experience a change in control.

In March 2018, the compensation committee of our Board of Directors approved the grant of options to purchase 217,293 shares of our common stock to Dr. Brady; 125,670 shares of our common stock to Mr. Tulipano; and 108,633 shares of our common stock to Dr. Clark. The exercise price for each of the options was $8.60 per share, which was the closing price of our common stock on The Nasdaq Capital Market on March 6, 2018. The options vest in equal monthly installments over four years of service following January 1, 2018 provided the named executive officer provides continuous service to us through such vesting dates. In addition, in March 2018, the compensation committee of our Board of Directors also granted a restricted stock unit award to Dr. Brady representing 96,144 shares of our common stock. This award vests in equal annual installments over four years of service following January 1, 2018.

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Outstanding Equity Awards at Fiscal 2017 Year-End

The following tables show certain information regarding outstanding equity awards, including, but not limited to, restricted stock unit awards, held by our named executive officers as of December 31, 2017. Except as indicated in the footnotes below, options granted to our named executive officers are generally immediately exercisable with respect to all of the option shares (whether vested or unvested), subject to our repurchase right in the event that the executive’s service terminates before vesting in such shares. For information regarding the vesting acceleration provisions applicable to the options held by our named executive officers, please see “Severance and Change in Control Benefits” below.

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Severance and Change in Control Benefits

Pursuant to their letter agreements and offer letters, in addition to any equity acceleration provided for in our Change in Control Plan (the CIC Plan) discussed below, if we terminate the employment of any of our named executive officers without cause or if such executive resigns for good reason, then such named executive will be eligible to receive:

Such payments are contingent on the officer’s executing and not revoking a release of claims against us.

“Cause” means an officer’s:

“Good Reason” means a resignation within 12 months after one of the following conditions has come into existence without the officer’s consent, but only if such officer has provided us with written notice of such condition within 90 days after it has come into existence and we have failed to cure such condition within 30 days after we receive such notice:

In March 2017, the compensation committee of our Board of Directors approved and established the CIC Plan, which provides for the accelerated vesting for outstanding unvested equity awards held by our eligible employees who are subject to a qualifying employment termination in connection with a change in control, including our executive officers. The CIC Plan provides for acceleration of 100% of the unvested equity held by our executive officers in the event the officer’s employment is terminated without cause, or the officer resigns for good reason, in each case within 3 months before or 12 months following a change in control. In connection with the adoption of the CIC Plan, Dr. Brady waived the “single trigger” acceleration of his equity awards on consummation of a change in control provided for in his offer letter. In addition, the CIC Plan shall replace any and all change of control provisions provided for in the equity or equity based awards granted to Drs. Brady and Clark prior to the establishment of the CIC Plan.

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For the purpose of the CIC Plan, the following terms have the definitions set forth below:

A termination for “cause” means termination by us of the executive officer’s employment by reason of the occurrence of any one or more of the following: (i) an act or acts of personal dishonesty taken by the executive officer and intended to result in substantial personal enrichment of the executive officer at the expense of the Company; (ii) repeated violations by the executive officer of the executive officer’s duties and obligations (other than as a result of incapacity due to physical or mental illness) which are demonstrably willful and deliberate on the executive officer’s part, which are committed in bad faith or without reasonable belief that such violations are in the Company’s best interests and which are not remedied in a reasonable period of time after receipt of written notice from the Company; (iii) indictment or plea of nolo contendere of the executive officer of a felony involving moral turpitude; or (iv) the material breach of the executive’s proprietary information and inventions agreement.

“Change in Control” means the occurrence of any of the following: (i) any “person” (as such term is used in Sections 13(d) and 14(d) of the Exchange Act) becomes the “beneficial owner” (as defined in Rule 13d-3 of the Exchange Act), directly or indirectly, of our securities representing more than fifty percent (50%) of the total voting power represented by our then-outstanding voting securities; (ii) the consummation of the sale or disposition by us of all or substantially all of our assets; (iii) the consummation of a merger or consolidation of our company with or into any other entity, other than a merger or consolidation which would result in the voting securities of the Company outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity or its parent) more than fifty percent (50%) of the total voting power represented by the voting securities of our company or such surviving entity or its parent outstanding immediately after such merger or consolidation; or the Incumbent Board ceases for any reason to constitute a majority of the members of our Board of Directors over a period of 12 months; provided, however, that if the appointment or election (or nomination for election) of any new member of our Board of Directors was approved or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member shall, for purposes of the CIC Plan, be considered as a member of the Incumbent Board. A transaction shall not constitute a Change in Control under the definition set forth in the preceding sentence if its sole purpose is to change the state of our incorporation or to create a holding company that will be owned in substantially the same proportions by the persons who held our securities immediately before such transaction.

“Good reason” means (i) a material diminution in the executive officer’s base salary or target bonus by more than 10%, except in connection with company-wide cost reduction; (ii) a material diminution in the executive officer’s authority, duties or responsibilities with respect to our company or any successor or acquiring entity, including, without limitation, any requirement that an officer who is our chief executive officer report to anyone other than to the Board of Directors of the ultimate parent entity of the Company (the “Ultimate Parent”) or that an executive officer (other than our chief executive officer) report to anyone other than the chief executive officer of the Ultimate Parent; (iii) a breach of a material provision of the executive officer’s employment or other written agreement governing employment with us (it being understand that a change in title without the executive officer’s consent shall be a material breach); or (iv) a relocation of the executive officer’s principal workplace by more than 50 miles from where the executive officer performed services prior to the relocation, without the executive officer’s prior consent. However, good reason shall not exist unless (i) the executive officer has given written notice to us within 90 days of the initial existence of the good reason event or condition(s) giving specific details regarding the event or condition; (ii) we have failed to cure such event or condition within 30-days of receiving such notice, and (iii) the executive officer resigns within 30 days of the expiration of the 30-day cure period provided for in clause (ii) provided that we have not cured the event or condition.

Employee Benefits and Perquisites

Our named executive officers will be eligible to participate in our health and welfare plans to the same extent as all other full-time employees. We do not provide our named executive officers with perquisites or other personal benefits other than reimbursement of certain healthcare premiums, as described in the Summary Compensation Table.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information with respect to the beneficial ownership of our common stock as of April 13, 2018 for:

The table below is based upon information supplied by officers, directors and principal stockholders and Schedule 13Gs and 13Ds filed with the SEC through April 13, 2018.

The percentage ownership is based upon 19,664,921 shares of common stock outstanding as of April 13, 2018.

For purposes of the table below, we deem shares of common stock subject to options that are currently exercisable or exercisable within sixty (60) days of April 13, 2018 and common stock subject to restricted stock unit awards that will vest within sixty (60) days of April 13, 2018 to be outstanding and to be beneficially owned by the person holding the options or restricted stock unit award for the purpose of computing the percentage ownership of that person, but we do not treat them as outstanding for the purpose of computing the percentage ownership of any other person. Except as otherwise noted, the persons or entities in this table have sole voting and investing power with respect to all of the shares of common stock beneficially owned by them, subject to community property laws, where applicable. Unless otherwise indicated, the address of each beneficial owner listed in the table below is c/o Aldeyra Therapeutics, Inc., 131 Hartwell Avenue, Suite 320, Lexington, Massachusetts 02421.

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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

In addition to the compensation arrangements with our directors and executive officers described elsewhere in this proxy statement, the following is a description of each transaction since January 1, 2017 and each currently proposed transaction in which:

Employment Agreements

We have entered into offer letters with our named executive officers. For more information regarding these agreements, see the section of this prospectus entitled “Executive Compensation — Narrative Disclosure to Compensation Tables.”

Indemnification Agreements

We have entered into separate indemnification agreements with our directors and executive officers, in addition to indemnification provided for in our amended and restated certificate of incorporation and amended and restated bylaws. These agreements, among other things, provide for indemnification of our directors and executive officers for certain expenses, judgments, fines and settlement amounts, among others, incurred by this person in any action or proceeding arising out of this person’s services as a director or executive officer in any capacity with respect to any employee benefit plan or as a director, partner, trustee or agent of another entity at our request. We believe that these provisions in our amended and restated certificate of incorporation and amended and restated bylaws and indemnification agreements are necessary to attract and retain qualified persons as directors and executive officers.

Equity Grants and Awards to Executive Officers and Directors

We have granted equity to our executive officers and certain of our directors as more fully described in the section entitled “Management — Director Compensation” and “Executive Compensation.”

Policies and Procedures for Related Party Transactions

Pursuant to our code of conduct and audit committee charter, any related party transaction or series of transactions with an executive officer, director, or any of such persons’ immediate family members or affiliates, in which the amount, either individually or in the aggregate, involved exceeds $120,000 must be presented to our audit committee for review, consideration and approval. All of our directors and executive officers are required to report to our audit committee any such related party transaction. In approving or rejecting the proposed transactions, our audit committee shall consider the relevant facts and circumstances available and deemed relevant to the audit committee, including, but not limited to the risks, costs and benefits to us, the terms of the transaction, the availability of other sources for comparable services or products and, if applicable, the impact on a director’s independence. Our audit committee shall approve only those transactions that, in light of known circumstances, are not inconsistent with Aldeyra’s best interests, as our audit committee determines in the good faith exercise of its discretion.

SECTION 16(a) BENEFICIAL OWNERSHIP REPORTING COMPLIANCE

Section 16(a) of the Securities Exchange Act of 1934, as amended, requires that our executive officers and directors and persons who own more than 10% of our common stock, file reports of ownership and changes of

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ownership with the SEC. Such directors, executive officers and 10% stockholders are required by SEC regulation to furnish us with copies of all Section 16(a) forms they file.

SEC regulations require us to identify anyone who filed a required report late during the most recent fiscal year. Based on our review of forms we received, or written representations from reporting persons, we believe that during fiscal 2017, all Section 16(a) filing requirements were satisfied on a timely basis.

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AUDIT COMMITTEE REPORT

The information contained in the following report of Aldeyra’s audit committee is not considered to be “soliciting material,” “filed” or incorporated by reference in any past or future filing by us under the Securities Exchange Act of 1934 or the Securities Act of 1933 unless and only to the extent that Aldeyra specifically incorporates it by reference.

Review of Audited Financial Statements for the Year Ended December 31, 2017

The audit committee has reviewed and discussed with Aldeyra’s management and BDO USA, LLP the audited financial statements of Aldeyra for the year ended December 31, 2017. The audit committee has also discussed with BDO USA, LLP the matters required to be discussed by Auditing Standard No. 1301, Communications with Audit Committees, as currently in effect and as adopted by the Public Company Accounting Oversight Board (“PCAOB”).

The audit committee has received and reviewed the written disclosures and the letter from BDO USA, LLP required by applicable requirements of the Public Company Accounting Oversight Board regarding the independent registered public accounting firm’s communications with the audit committee concerning independence, and has discussed with BDO USA, LLP its independence from us.

Based on the review and discussions referred to above, the audit committee recommended to the Board of Directors that the audited financial statements be included in the 2017 Annual Report for filing with the SEC.

Submitted by the audit committee of the Board of Directors:

Marty Joyce (Chair)

Ben Bronstein, M.D.

Jesse I. Treu, Ph.D.

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OTHER MATTERS

We know of no other matters to be submitted at the Annual Meeting. If any other matters properly come before the Annual Meeting, it is the intention of the persons named in the proxy card to vote the shares they represent as Aldeyra may recommend.

It is important that your shares be represented at the Annual Meeting, regardless of the number of shares that you hold. You are, therefore, urged to vote at your earliest convenience on the Internet or by telephone as instructed, or by executing and returning a proxy card, if you have requested one, in the envelope provided.

THE BOARD OF DIRECTORS

Lexington, Massachusetts

April 25, 2018

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APPENDIX A

AMENDMENT NO. 2 TO THE ALDEYRA THERAPEUTICS, INC.

2013 EQUITY INCENTIVE PLAN

Aldeyra Therapeutics, Inc., a Delaware corporation (the “Company”), adopted the 2013 Equity Incentive Plan on September 8, 2013 (the “Plan”). Unless otherwise defined herein, all capitalized terms shall have the meaning set forth in the Plan.

1. Section 3.2 of the Plan shall be amended and restated in its entirety to read as follows:

“3.2 Annual Increase in Shares. As of the first business day of each fiscal year of the Company during the term of the Plan, commencing on the first day of the Company’s 2019 fiscal year, the aggregate number of Common Shares that may be issued under the Plan shall automatically increase by a number equal to the lower of (a) 6% of the total number of Common Shares outstanding on the last calendar day of the prior fiscal year or (b) a number of Common Shares determined by the Board.”

2. The following new subsections 3.5(e) and 3.5(f) shall be added to the Plan:

“(e) The maximum annual aggregate grant date fair value (as determined in accordance with Financial Accounting Standards Board Accounting Standards Codification Topic 718 (“Topic 718”), or any successor thereto) of Options and SARs that may be granted under this Plan to an Outside Director as compensation for services as an Outside Director during a calendar year shall not exceed $500,000.

(f) The maximum aggregate grant date fair value (as determined in accordance with Topic 718, or any successor thereto) of Common Shares issued as either Restricted Shares and Stock Units that may be granted under this Plan to an Outside Director as compensation for services as an Outside Director during a calendar year shall not exceed $500,000.”

Except as expressly amended hereby, the Plan shall remain unchanged and in full force and effect and is hereby ratified and confirmed.

Adopted by the Company’s Board of Directors: March 6, 2018

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