AGENUS INC.

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

A list of stockholders entitled to vote will be open for examination by any stockholder for any purpose germane to the 2018 Annual Meeting of Stockholders for ten days before the meeting during ordinary business hours at our principal offices at 3 Forbes Road, Lexington, Massachusetts 02421.

It is important that your shares be represented at the 2018 Annual Meeting of Stockholders. Therefore, whether or not you plan to attend the meeting, please complete your proxy and return it to us. If you attend the meeting and wish to vote in person, your proxy will not be used. You may also vote your shares over the internet or by telephone. Instructions for internet or telephonic voting are printed on your proxy card.

April 26, 2018

TABLE OF CONTENTS

AGENUS INC.

3 Forbes Road

Lexington, Massachusetts 02421

Telephone: (781) 674-4400

PROXY STATEMENT

April 26, 2018

This proxy statement contains information about the 2018 Annual Meeting of Stockholders of Agenus Inc. (the “2018 Annual Meeting”), including any postponements or adjournments of the meeting. The 2018 Annual Meeting will be held at Agenus Inc., 3 Forbes Road, Lexington, Massachusetts 02421 on June 20, 2018 at 5:00 P.M., Eastern Time.

In this proxy statement, we refer to Agenus Inc. as “Agenus,” “us,” “we” or the “Company.”

This proxy statement and solicitation is being made on behalf of the Board of Directors of Agenus Inc.

In accordance with the “notice and access” rules approved by the Securities and Exchange Commission (“SEC”) and in connection with the solicitation of proxies by our Board of Directors, on or about April 26, 2018 we first sent a Notice of Internet Availability of Proxy Materials and provided access to our proxy materials (consisting of this proxy statement, our Annual Report on Form 10-K for the year ended December 31, 2017 and a form of proxy) over the internet to each stockholder entitled to vote at the 2018 Annual Meeting. We intend to mail to requesting stockholders full sets of our proxy materials (consisting of this proxy statement, our Annual Report on Form 10-K for the year ended December 31, 2017 and a form of proxy) on or about April 26, 2018.

Our Annual Report on Form 10-K for the year ended December 31, 2017 is also available on our corporate website at http://investor.agenusbio.com/SEC-Filings and through the SEC’s EDGAR system at http://www.sec.gov. To request a printed copy of our Annual Report on Form 10-K, which we will provide to you without charge, write to Investor Relations, Agenus Inc., 3 Forbes Road, Lexington, Massachusetts 02421. No material on our website is part of this proxy statement.

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VOTING PROCEDURES

YOUR VOTE IS IMPORTANT. PLEASE TAKE THE TIME TO VOTE. Stockholders have a choice of voting over the internet, by telephone, by mail using a proxy card, or in person at the 2018 Annual Meeting. Please refer to the proxy card or other voting instructions included with these proxy materials for information on the voting methods available to you. If you vote over the internet, by telephone, or in person at the 2018 Annual Meeting, you do not need to return your proxy card.

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PROPOSAL 1—ELECTION OF DIRECTORS

The Board of Directors has nominated the individual listed below for election as a Class III director. The nominee currently serves as a Class III director.

Our Board of Directors (the “Board”) is divided into three classes. One class is elected each year and members of each class hold office for three-year terms. The Board currently consists of six members. Two members are Class I directors, with terms expiring at the 2019 Annual Meeting. Two members are Class II directors, with terms expiring at the 2020 Annual Meeting of Stockholders. Two members are Class III directors, with terms expiring at the 2018 Annual Meeting of Stockholders. The Board has nominated Wadih Jordan, a current Class III director, for re-election to a term expiring at the 2021 Annual Meeting of Stockholders. Shalini Sharp, a current Class III director, is not being nominated for re-election at the 2018 Annual Meeting of Stockholders. Ms. Sharp will cease serving on the Board immediately following the 2018 Annual Meeting of Stockholders, and the Board will be reduced to five members.

For more information on nomination of directors, see “Corporate Governance and Nominating Committee” below in the section entitled “Our Corporate Governance—Committees of the Board.”

Your vote is requested in favor of Wadih Jordan, the nominee listed below, as a Class III director. The nominee has indicated his willingness to serve, if elected, but if he should be unable or unwilling to serve, proxies may be voted for a substitute nominee designated by the Board.

There are no family relationships between or among any of our executive officers, directors, or nominee for director.

Below are the names and certain information about each member of the Board (other than Ms. Sharp), including the nominee for election as a Class III director:

NOMINEE FOR CLASS III DIRECTOR—TERM TO EXPIRE IN 2018

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CLASS I DIRECTORS—TERMS TO EXPIRE IN 2019

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CLASS II DIRECTORS—TERMS TO EXPIRE IN 2020

Vote Required

The nominee for director receiving the highest number of votes FOR election will be elected as a director. This is called a plurality. If your shares are held by your broker, bank, or nominee in “street name” and if you do not vote your shares or instruct your broker, bank, or nominee how to vote with respect to this item, your unvoted shares will be counted as “broker non-votes.” Abstentions and “broker non-votes” are not counted for purposes of electing directors. You may vote FOR the nominee or WITHHOLD your vote from the nominee. Votes that are withheld will not be included in the vote tally for the election of directors and will have no effect on the results of the vote.

The Board of Directors recommends a vote FOR the nominee for Director.

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OUR CORPORATE GOVERNANCE

Our Commitment to Good Corporate Governance

We believe that good corporate governance and an environment of high ethical standards are important for Agenus to achieve business success and to create value for our stockholders. The Board is committed to high governance standards and to continually working to improve them. We continue to review our corporate governance practices in light of ongoing changes in applicable law and evolving best practices.

Role of Our Board

The Board monitors our overall corporate performance, the integrity of our financial controls, risk management and legal compliance procedures. It appoints senior management and oversees succession planning and senior management’s performance and compensation. The Board also oversees our short- and long-term strategic and business planning, and reviews with management its business plan, financing plans, budget, and other key financial and business objectives.

Members of the Board keep informed about our business through discussions with our Chief Executive Officer and other members of our senior management team, by reviewing materials provided to them by management on a regular basis and in preparation for Board and committee meetings, and by participating in meetings of the Board and its committees. Senior management regularly reviews key portions of our business with the Board. These practices afford the Board members the opportunity to actively participate in risk management assessment and raise questions and engage in discussions with management regarding areas of potential risk. The Audit and Finance Committee of the Board reviews the risk management practices of the Company and both the Corporate Governance and Nominating Committee and the Audit and Finance Committee receive an annual report from the Company’s Chief Compliance Officer outlining areas of compliance focus and proposed recommendations. Additionally, the Compensation Committee reviews the Company’s executive compensation program and the incentives created by the executive compensation program, to assess whether our compensation arrangements encourage excessive risk-taking by our executives.

We introduce our executives and other employees to the Board so that the Board can become familiar with our key talent. Timothy R. Wright, our Lead Director, introduces each new Board member to our Corporate Governance policies and their responsibilities to the Company as a director. Each Board member receives a Board of Directors handbook that provides the director with a summary of these practices and policies.

Board Meetings and Attendance

In 2017, the Board met nine times and acted by written consent once. During 2017, each of our directors attended at least 75% of (i) the total number of meetings of the Board held during the period during which the director served and (ii) all meetings of committees of the Board on which the director served during the periods the director served. All of our Board members attended our 2017 Annual Meeting of Stockholders. We expect each of our Board members to attend the 2018 Annual Meeting.

Governance Guidelines

The Board is guided by our Guidelines on Significant Corporate Governance Issues (our “Governance Guidelines”). We believe our Governance Guidelines demonstrate our continuing commitment to good corporate governance. The Board reviews our Governance Guidelines from time to time, as needed, and at least once annually. Our Governance Guidelines are posted on the corporate governance section of our website at http://investor.agenusbio.com/board-committees. No material on our website is part of this proxy statement.

Performance of Our Board

We consider it important to continually evaluate and improve the effectiveness of the Board, its committees and its individual members. We do this in various ways. Each year, the Lead Director surveys the Board

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members to assess the effectiveness of the Board and its committees. Using these surveys, the Lead Director assesses the Board’s performance and the performance of individual members, and reports his conclusions to the full Board. The assessment also evaluates the Board’s effectiveness in reviewing executive management, conducting appropriate oversight and adding value to Agenus. Each of the Board’s standing committees also conducts annual self-evaluations.

At each Board meeting, each Board member has the opportunity to assess the effectiveness of the materials presented and the conduct of the meeting, and to offer suggestions for improvement at future meetings.

Code of Business Conduct and Ethics

The Board originally adopted our Code of Business Conduct and Ethics (the “Code of Ethics”) in 2003. The Board reviewed, revised, and updated the Code of Ethics most recently in January 2018. The Code of Ethics applies to all members of the Board and all employees of Agenus, including our Chief Executive Officer and Principal Financial and Accounting Officer. Among other matters, our Code of Ethics prohibits the members of the Board and all employees of Agenus from buying or selling our securities while in possession of material, non-public information about the Company. Our Code of Ethics is posted on the corporate governance section of our website at http://investor.agenusbio.com/board-committees. No material on our website is part of this proxy statement. We intend to post on our website all disclosures that are required by law or Nasdaq listing rules concerning any amendments to, or waivers from, our Code of Ethics. Stockholders may request a free copy of our Code of Ethics by writing to Investor Relations, Agenus Inc., 3 Forbes Road, Lexington, MA 02421.

Independence of Directors

Our Governance Guidelines and Nasdaq listing rules provide that a majority of the Board should be composed of independent directors. The Corporate Governance and Nominating Committee annually reviews the independence of the directors and reports to the Board which directors it recommends that the Board determine are independent. The Board then makes the final determination. The Board takes into account Nasdaq listing rules, applicable laws and regulations, and other factors in making its determinations including potential conflicts of interest, transactions, and other relationships that would reasonably be expected to compromise a director’s independence. The Board has determined that Mr. Corvese, Mr. Jordan, Ms. Sharp, Mr. Wiinberg, and Mr. Wright are currently independent directors. Dr. Armen is currently not an independent director because he is employed as our Chief Executive Officer. In making independence determinations with regard to other directors, the Board considered transactions between us and a director or a director’s affiliates and any positions a director holds with entities with commercial relationships with us.

Executive Sessions of Independent Directors

Our independent directors typically meet in executive session without management present immediately prior to regularly scheduled Board meetings and at least quarterly. Four such meetings were held during 2017.

Leadership Structure of the Board

Mr. Wright, an independent director, serves as the Lead Director of the Board and as Chair of the Corporate Governance and Nominating Committee. Mr. Wright also serves on the Compensation Committee, the Audit and Finance Committee and the Executive Committee. In addition to the duties of all directors, the specific responsibilities of the Lead Director include: (i) acting as chair of the Corporate Governance and Nominating Committee; (ii) developing the agenda for and presiding over all executive sessions of the independent directors; (iii) acting as principal liaison between the independent directors and the Chief Executive Officer on sensitive issues and raising at any meeting of the Board items that are not appropriately or best put forward by the Chief Executive Officer; and (iv) communicating to the Chief Executive Officer the independent directors’ annual evaluation of the Chief Executive Officer. The Company’s Chief Executive Officer serves as the Chairman of the

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Board. We believe that the Company’s Chief Executive Officer is best situated to serve as Chairman because he is the director most familiar with the Company’s business, and most capable of effectively identifying strategic priorities and leading the discussion and execution of our Company’s strategy. Our independent directors and management have different perspectives and roles in strategy development. The Company’s independent directors bring experience, oversight, and expertise from outside the Company and from inside and outside the Company’s industry, while the Chief Executive Officer brings Company-specific experience and expertise. To assure effective independent oversight, the Company has adopted a number of governance practices, including:

While there may be circumstances in the future that would lead the Company to separate the offices of Chairman and Chief Executive Officer, we do not believe this is currently necessary due to the nature and size of the operations of the Company, the overall independence of the Board from management, and the strength of the Lead Director’s role on the Board.

Committees of the Board

The Board currently has four standing committees: the Audit and Finance Committee, the Compensation Committee, the Corporate Governance and Nominating Committee and the Executive Committee. The Board also appoints from time to time ad hoc committees to address specific matters.

Audit and Finance Committee

The Audit and Finance Committee consists entirely of independent directors within the meaning of the Nasdaq listing rules and the requirements contemplated by Rule 10A-3 of the Securities Exchange Act of 1934, as amended (the “1934 Act”). During 2017, the Audit and Finance Committee consisted of Mr. Corvese (Chair), Dr. Malik, Mr. Jordan and Mr. Wright. Dr. Malik retired from the Board on June 28, 2017, and Mr. Jordan joined the Audit and Finance Committee on June 29, 2017. The Board has determined that Mr. Corvese qualifies as an audit committee financial expert. For a description of Mr. Corvese’s relevant experiences that qualify him as an audit committee financial expert, please see his biography on page 8. The Audit and Finance Committee’s primary function is to assist the Board in monitoring the integrity of our consolidated financial statements and our system of internal control. The Audit and Finance Committee has direct responsibility for the appointment, independence, and monitoring of the performance of our independent registered public accounting firm. The committee is responsible for pre-approving any engagements of our independent registered public accounting firm. The committee also reviews our risk management practices, strategic tax planning, preparation of quarterly and annual financial reports, and compliance processes.

The Audit and Finance Committee members meet regularly with our independent registered public accounting firm, without management present and with members of management in separate private sessions, to discuss any matters that the committee or these individuals believe should be discussed privately with the committee, including any significant issues or disagreements concerning our accounting practices or consolidated financial statements. The committee also reviews the Code of Ethics annually, and periodically meets with our Chief Compliance Officer. The committee conducts a meeting each quarter to review our consolidated financial

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statements prior to the public release of earnings. The committee has the authority to engage special legal, accounting or other consultants to advise the committee. The committee also has the authority to delegate to subcommittees any responsibilities of the full committee. The Audit and Finance Committee charter is posted on the corporate governance section of our website at http://investor.agenusbio.com/board-committees. No material on our website is part of this proxy statement. Please also see the Report of the Audit and Finance Committee on page 66.

Compensation Committee

The Compensation Committee consists entirely of independent directors within the meaning of applicable Nasdaq listing rules. During the entirety of 2017, Mr. Jordan (Chair), Mr. Corvese and Mr. Wright were members of the Compensation Committee. The committee’s primary responsibilities are to address our executive officers’ and other key employees’ development, retention, and performance and to oversee compensation and benefit matters. It reviews and approves compensation policies for Agenus to ensure that our compensation strategy supports organizational objectives and stockholder interests and does not create incentives for inappropriate risk-taking. The committee reviews, determines and approves the compensation of the Chief Executive Officer, all other executive officers and certain other key employees. It also reviews and recommends compensation for members of the Board. Additionally, the committee approves and recommends, and suggests material changes to, executive and key employee incentive compensation and benefits policies, including equity and director compensation plans.

The Compensation Committee considers appropriate companies for compensation comparison purposes and retained an outside compensation consultant in 2017, Radford, an Aon Hewitt Company—a division of Aon Corporation (“Radford”), to evaluate our executive compensation program and to provide market reference information relating to compensation and benefits. The committee has the authority to retain legal, accounting, or other consultants to advise the committee. The committee also has the authority to delegate to subcommittees any responsibilities of the full committee. The Compensation Committee charter is posted on the corporate governance section of our website at http://investor.agenusbio.com/board-committees. No material on our website is part of this proxy statement. Please also see the Compensation Discussion and Analysis starting on page 16, and the accompanying Compensation Committee Report on page 30. Radford does not provide any services to the Company or the Compensation Committee other than those described above. After consideration of the six independence assessment factors provided under the listing rules of Nasdaq, the Compensation Committee determined that Radford, as an advisor to the Compensation Committee during 2017, was independent and that the work performed by Radford did not raise any conflicts of interest in 2016 that would preclude the Compensation Committee from reviewing and considering Radford’s analyses when making compensation decisions.

Corporate Governance and Nominating Committee

The Corporate Governance and Nominating Committee consists entirely of independent directors within the meaning of applicable Nasdaq listing rules. During the entirety of 2017, the Corporate Governance and

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Nominating Committee consisted of Mr. Wright (Chair), Ms. Sharp and Mr. Wiinberg. Ms. Sharp will no longer serve on the Board or the Corporate Governance and Nominating Committee following the 2018 Annual Meeting. The Corporate Governance and Nominating Committee is responsible for recommending to the Board policies relating to the conduct of Board affairs, the process for annual evaluation of the Board and the Chief Executive Officer, issues of corporate public responsibility, and overseeing the Company’s management succession planning process. It periodically evaluates the composition of the Board, the contributions of individual directors, and the Board’s effectiveness as a whole. The committee reviews the Company’s ethics and compliance activities under the Code of Ethics and meets periodically with our Chief Compliance Officer, including meeting, as needed, for separate private sessions with the Chief Compliance Officer without other members of management present.

The Corporate Governance and Nominating Committee recommends to our full Board individuals to serve as directors. The committee recommends to the Board guidelines and criteria for Board membership and reviews with the Board, on a periodic basis, the appropriate skills and characteristics required of Board members in the context of the then current needs of Agenus. The committee is responsible for reviewing with the Board the appropriate personal characteristics and professional competencies preferred of Board members, who are expected to work together as a team to properly oversee our strategies and operations. In general, all directors are expected to possess certain personal characteristics necessary to create a highly functional and collegial Board, which include personal and professional integrity, practical wisdom and mature judgment, an inquisitive and objective perspective, and time availability for performing the duties of a director.

The Board, as a group, is expected to encompass a range of talents, ages, skills, diversity, and expertise sufficient to provide sound and prudent guidance with respect to the operations and interests of our business. Examples of desired professional competencies include accounting and financial literacy, industry knowledge, medical or scientific knowledge, and management experience. When evaluating potential new Board appointments, the Corporate Governance and Nominating Committee considers these factors, but does not have any fixed criteria for candidates it recommends because the Board believes that a flexible evaluation process allows the committee to make sound judgments based on the needs of the organization and specific attributes of each candidate without a need for a formal policy on diversity. Candidates should also be enthusiastic about service on our Board and working collaboratively with existing Board members to create value for all of our stockholders.

The Corporate Governance and Nominating Committee does not have a formal policy with regard to the consideration of director candidates recommended by stockholders because it does not believe such a policy is necessary given that no unaffiliated stockholder has ever recommended a director candidate. When considering director candidates, the Corporate Governance and Nominating Committee, in consultation with the Chief Executive Officer and full Board, considers the current strengths on the existing Board, the current needs of the organization, and anticipated future activities and requirements of both the Board and the organization as a whole. Historically, director candidates have been generally identified primarily through referrals and the executive network pool of the Board and senior executives. If the committee were to receive a recommendation for a director candidate from a stockholder, the committee expects that it would evaluate such a candidate using the criteria described above. The committee will consider a recommendation only if appropriate biographical information and background material is provided on a timely basis, accompanied by a statement as to whether the stockholder or group of stockholders making the recommendation has beneficially owned more than 5% of our common stock for at least one year as of the date that the recommendation is made. To submit a recommendation for a nomination, a stockholder may write to the Lead Director, Agenus Inc., 3 Forbes Road, Lexington, Massachusetts 02421, Attention: Lead Director c/o Chief Compliance Officer.

In addition, our by-laws permit stockholders to nominate individuals, without any action or recommendation by the committee or the Board, for election as directors at an annual meeting of stockholders. For a description of this by-law provision, see Additional Information on page 67 of this proxy statement. The charter of the Corporate Governance and Nominating Committee is posted on the corporate governance section of our website at http://investor.agenusbio.com/board-committees. No material on our website is part of this proxy statement.

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Communications with the Board

You may contact the Board or any committee of the Board by writing to Board of Directors (or specified committee), Agenus Inc., 3 Forbes Road, Lexington, Massachusetts 02421, Attn: Lead Director c/o Chief Compliance Officer. You should indicate on your correspondence that you are an Agenus stockholder. Communications will be distributed to the Lead Director, the appropriate committee chairman, or other members of the Board or executive management, as appropriate, depending on the facts and circumstances stated in the communication received. Executive management will generally determine the proper response to inquiries of a commercial nature, which generally will not be forwarded to the Lead Director. Inquiries regarding accounting, internal controls over financial reporting, or auditing matters will be forwarded to the Chair of the Audit and Finance Committee, and inquiries involving matters governed by the Code of Ethics will be forwarded to the Chair of the Corporate Governance and Nominating Committee and the Chief Compliance Officer.

Compensation Committee Interlocks and Insider Participation

The members of the Compensation Committee for the year ended December 31, 2017 were Mr. Jordan (Chair), Mr. Corvese, and Mr. Wright. No member of the Compensation Committee was at any time during 2017, or formerly, an officer or employee of Agenus or any subsidiary of Agenus. No executive officer of Agenus has served as a director or member of a compensation committee (or other committee serving an equivalent function) of any other entity while an executive officer of that other entity served as a director of Agenus or member of the Compensation Committee.

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COMPENSATION DISCUSSION AND ANALYSIS

This section discusses the principles underlying our policies and decisions with respect to the compensation of our executives who are named in the “Summary Compensation Table” below, who are referred to throughout this proxy statement as our “named executive officers,” and the material factors relevant to an analysis of these policies and decisions. Our named executive officers for 2017 are:

Executive Summary

Our executive compensation program is designed to attract and retain the highest caliber talent, reward strong performance and align incentives with the creation of long-term stockholder value, taking into consideration the Company’s resource constraints. The short-term compensation (base salary and target annual incentive bonuses) of our named executive officers is positioned at approximately the 50^th percentile of our compensation peer group, and our long-term incentive programs are designed to preserve our cash resources, promote long-term decision-making and value creation and reward stock price appreciation.

Our performance in 2017 met the majority of our annual goals that had been established under our annual bonus plan, despite challenging circumstances, including limited financial and human resources, aggressive timelines and third-party competition. As more specifically described below, during 2017 we:

We believe that our incentive compensation programs were administered in a manner consistent with our operating performance, long-term objectives, and compensation philosophy. Based on the Company’s overall performance in 2017, the annual incentive bonuses paid to our named executive officers (other than Dr. Stein and Dr. Cuillerot) for 2017 performance ranged from 124% to 150% of their target bonus amounts.

Compensation Philosophy

Our executive compensation program is designed to attract and retain the highest caliber executive talent and reward and align incentives with the creation of long-term stockholder value, while effectively managing the risks and challenges inherent to a biotechnology company of our size and stage of development. We offer a

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compensation package that combines short- and long-term components, cash and equity, and fixed and variable payments, in proportions that we believe appropriately incentivize our executives to achieve the following goals:

Our general philosophy is to emphasize equity over cash compensation and long-term over short-term compensation. Our executive compensation program not only aims to be competitive in our industry, but also to be fair relative to other professionals within our organization. Our executives’ base salaries, target annual incentive bonus levels, and target annual long-term incentive award values are set at levels that are competitive with those of our peer group. Executives have the opportunity to earn above-market pay for above-market performance as measured against our peer group. See “Competitive Market Review” below for further information on our peer group.

We continually review our executive compensation program in order to ensure that it rewards our executives for achieving our goals and objectives in a manner consistent with our philosophy and values and at levels that are competitive with our peer group. In designing our executive compensation program, we also seek to reward executive decisions that are consistent with the Company’s goals and objectives and that deliver positive stockholder returns. We evaluate and reward our executives based on the Company’s performance, their contribution to the achievement of short- and long-term goals and objectives, and their ability to take advantage of unique opportunities and overcome difficult challenges within our business. We believe that our mix of short-term and long-term incentives, and our process of evaluating performance results, assist us in managing risk-taking that may result from our compensation program and aligning our employees’ behavior with our overall business plan and the interests of our stockholders. Our Compensation Committee has concluded that our current compensation programs present no risks that are reasonably likely to have a material adverse effect on the Company.

At the Company’s 2017 Annual Meeting of Stockholders, our stockholders had the opportunity to cast an advisory vote (a “say-on-pay” vote) on the compensation of our executives as disclosed in our proxy statement for that meeting. Our stockholders approved the say-on-pay proposal by an affirmative vote of 96.6% of the votes cast on that proposal. Our Compensation Committee believes this affirms stockholders’ support of the Company’s approach to executive compensation, and this approach has not changed since the 2017 Annual Meeting of Stockholders. Our Compensation Committee will continue to consider the outcome of the Company’s say-on-pay votes when making future compensation decisions for our executives.

At the Company’s 2017 Annual Meeting of Stockholders, our stockholders also had the opportunity to cast an advisory vote (a “say-on-frequency” vote) on how often the Company should include a say-on-pay proposal in its proxy statements for future annual meetings. Our stockholders approved a proposal to hold say-on-pay votes once every three years. Accordingly, our Board adopted a policy to hold say-on-pay votes every three years until the next required “say-on-frequency” advisory vote, which is to be held at our 2023 Annual Meeting of Stockholders.

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Competitive Market Review

The market for top-tier executive talent in the biotechnology industry is highly competitive. In order to attract and retain a superior leadership team we need to draw upon a pool of talent that is highly sought-after by both large and established pharmaceutical and biotechnology companies in and outside our geographic area and by other life science companies.

We believe we have a competitive advantage in our ability to offer significant upside potential through stock options and other equity-based awards. In addition, we offer market-competitive cash compensation levels through base salaries and cash bonus opportunities. We also compete on the basis of our vision of future success, our culture and values, the cohesiveness and productivity of our teams, and the excellence of our scientists and management personnel.

In order to succeed in attracting highly-talented executives, we continuously monitor market trends and draw upon surveys prepared by Radford, our Compensation Committee’s independent compensation consultant, custom research developed by Radford, and other nationally-recognized surveys. Our Compensation Committee reviews data that analyzes various cross-sections of our industry as well as relevant geographical areas.

Market References: How We Define Market and How We Use Market Compensation Data. Our Compensation Committee has engaged Radford since 2016 as its independent compensation consultant to evaluate our executive compensation program and compare it to other programs in the market.

Defining the Market. For 2017, we used two market references to evaluate our executive compensation program against those in the market:

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Determining Market Levels and Specific Comparisons. We compare our executive compensation program and amounts of compensation against our peer group by reviewing each compensation component (measured at target in the case of annual and long-term incentive opportunities) and total compensation. The comparisons made in this process are used to determine our approximate position relative to the appropriate market reference by each element of compensation and in total.

Total Compensation

We intend to continue our strategy of compensating our executives at competitive levels, with the opportunity to earn above-market pay for above-market performance. We will continue to emphasize long-term equity incentives and performance-based incentive compensation to maintain our competitive pay philosophy.

For 2017, the total compensation for our named executive officers generally fell between the 40^th and 60^th percentile of total compensation paid to executives holding equivalent positions in our peer group. For this purpose, total compensation includes annual base salary, target annual incentive bonus and the grant date value of equity awards. We believe that the total compensation for our named executive officers was reasonable given our corporate performance and our financial circumstances.

The competitive posture of our actual annual compensation paid or earned versus market references will vary year to year based on Company and individual performance, as well as the performance of our peer group and the respective levels of compensation paid by peer group companies to their executives. We expect to continue targeting total compensation at approximately the 50^th percentile of our peer group, with an emphasis on performance-based compensation. Further, in light of our compensation philosophy, we believe that the total compensation package for our executives should continue to consist of base salary, annual incentive bonuses, long-term equity-based incentive compensation, and certain other benefits.

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Role of Our Compensation Committee

Our Compensation Committee approves, administers, and interprets our executive compensation and benefit programs, including awards under our 1999 Equity Incentive Plan (as amended) and our Amended and Restated 2009 Equity Incentive Plan (the “2009 Equity Incentive Plan”). Our Compensation Committee is appointed by our Board, and consists entirely of directors who are “non-employee directors” for purposes of Rule 16b-3 under the 1934 Act. Our Compensation Committee is comprised of Mr. Jordan (Chair), Mr. Corvese and Mr. Wright.

Our Compensation Committee seeks to ensure that our executive compensation program is consistent with our compensation philosophy and our Governance Guidelines, and determines the executive compensation packages offered to our executives.

Executive Compensation Program

Components of our Executive Compensation Program

Our executive compensation program consists of the following four components (each described in more detail below):

To determine levels of overall executive compensation, our Compensation Committee balances individual, functional area, and company-wide goals and achievements. For purposes of setting the annual goals under our annual bonus program, each executive participates in establishing the objectives of our Company as a whole and offers his or her views as to the goals of each functional area, insofar as those goals impact the individual executive’s own functional area. After the end of the relevant year, we also ask our executives to provide feedback not only on their own performance and that of their particular functional area, but also of other functional areas and our entire organization. We see this process both as the optimal way of assembling accurate information regarding expected and actual performance, as well as an integral part of our culture of collaborative, team-oriented management. Final goals and objectives for our annual bonus program are approved by the Board.

In 2017, our Company goals and objectives included:

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At the end of each year, our executives and our Compensation Committee evaluate the achievement of the Company’s goals and objectives and begin discussions regarding goals and objectives for the next year. Incentive compensation, based on the achievement of goals and objectives, may be awarded in the form of an annual incentive bonus and/or equity-based awards. Equity-based awards are used to align the interests of our executives with those of our stockholders and to promote a long-term performance perspective and incentivize the achievement of our long-term goals and objectives.

The general structure of our executive compensation program is consistent with that for non-executive members of the Agenus management team.

Short-Term Compensation.

Our short-term compensation program consists of base salary and annual incentive bonuses. Base salary provides a fixed rate of base compensation to recognize the experience, skills, knowledge, and responsibilities of each executive, and takes into account competitive market conditions.

Base Salary: Base salaries for our executives are generally positioned at or around the 50^th percentile of our peer group (see “Competitive Market Review” above for further information on our peer group). In establishing the base salaries of our executives, our Compensation Committee (with input from our Chief Executive Officer, other than with respect to his own base salary) takes into account a number of factors, including the executive’s seniority, experience, position and functional role, and responsibilities.

We also consider the following factors when determining base salary:

The base salaries of our executives are reviewed on an annual basis, and adjustments are made to reflect the executive’s performance, as well as competitive market conditions. Increases are considered within the context of our overall annual financial position before more specific individual and market competitive factors are considered. We do not apply specific formulas to determine base salary increases. In 2017, our Compensation Committee approved base salary increases for Dr. Armen, Dr. Cuillerot, Dr. Duncan and Ms. Valentine, as described below under “Compensation Actions for our Named Executive Officers.” Base salaries for Dr. Stein and Ms. Klaskin were not increased in 2017.

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Annual Incentive Bonuses: Annual incentive bonuses for our executives are based on achievement of the Company’s goals and objectives as well as individual performance as outlined in our Executive Incentive Plan. Each executive is eligible to receive an annual incentive bonus ranging from 0-200% of his or her target bonus based on our Compensation Committee’s evaluation of the achievement of Company goals and objectives and such individual’s performance. The Company’s annual goals and objectives are set at the beginning of each year and are reviewed and approved by our Compensation Committee and the Board. At the end of the year, management prepares a report outlining the extent to which Company goals and objectives were achieved and presents that report to our Compensation Committee along with a recommendation on the executives’ annual incentive bonus payout levels, as a percentage of their target bonuses. Our Compensation Committee evaluates the report, along with any relevant supporting documentation, and considers it in the context of any change in facts or circumstances that could have impacted goal attainment throughout the year. From time to time, our Compensation Committee may request supplemental information from management to support the committee’s evaluation. Based on this evaluation, as well as the Company’s available financial resources, our Compensation Committee determines the appropriate level for the executives’ annual incentive bonus payouts. There is no quantifiable formula or weighting of goals. As a result, our Compensation Committee exercises discretion in establishing the level of the executives’ bonus payout, taking into account the level of achievement of the Company goals as a whole. Once determined, the recommended bonus payout level is applied to each executive’s target bonus percentage to establish his or her annual incentive bonus payout. Our Compensation Committee may exercise further discretion to adjust the actual bonus paid to any individual executive based on his or her individual performance and its impact on the Company’s overall performance (with input from our Chief Executive Officer, other than with respect to his own bonus), which it did in 2017, as described below under “Compensation Actions for our Named Executive Officers.”

For 2017, each of our executives were eligible to receive a target annual incentive bonus, expressed as a percentage of his or her base salary. Target bonus amounts were set based on competitive benchmarks, the Committee’s assessment of overall Company performance and the individual’s unique contribution to the Company’s overall performance. In March 2017, the Compensation Committee increased Dr. Duncan’s annual incentive bonus target from 30% to 40% of his base salary, as described below under “Compensation Actions for our Named Executive Officers.” Annual incentive bonus targets for all other named executive officers were unchanged in 2017.

In determining the annual incentive bonus payouts for our executives for 2017, our Compensation Committee determined that the majority of the stated goals and objectives for 2017, as described above, were accomplished, and considered the following additional key company achievements: (i) launched Phase 2 trial with the combination of AGEN1884 and Keytruda in patients with 1L NSCLC and over 50% PD-L1 expression and (ii) launched AgenTus Therapeutics, our cell therapy subsidiary.

Our Compensation Committee gave weight to the fact that these accomplishments were made in a challenging economic environment in which the management team was under substantial resource constraints, and that the accomplishments in 2017 were critical in advancing the development of our diverse portfolio, reducing our reliance on contract manufacturing organizations, effectively managing our cost structure and advancing the Company towards potential commercialization. The range in individual annual incentive bonus payouts reflects each executive’s unique contribution to the Company’s overall performance, as determined by our Compensation Committee. The table below shows the following for each of our named executive officers in 2017: target annual incentive bonus (as a percentage of base salary), actual annual incentive bonus received (as a percentage of base salary) and actual annual incentive bonus received (as a percentage of target). Dr. Stein retired as President of R&D and became a senior R&D advisor to the Company effective April 1, 2017 and upon his retirement forfeited any entitlement to a 2017 annual incentive bonus. Dr. Cuillerot’s employment ended on

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January 17, 2018, and, in connection with his termination of employment, he forfeited any entitlement to a 2017 annual incentive bonus.

Long-Term Incentives.

Our long-term incentives consist of time-vesting and performance-vesting stock options, restricted stock grants and performance shares. During 2017, only stock options and performance shares were granted to our executives. Performance shares reward performance and the achievement of key milestones that are important to our success. Stock options are performance-based because no value is created unless the value of our common stock appreciates after grant. We also grant stock options that are subject to performance-based vesting to further drive the achievement of key business objectives. Equity-based awards also support an ownership culture and thereby encourage our executives to take actions that are in the best interests of the Company’s long-term success. Our Compensation Committee grants equity incentives to our executives and employees generally to enable them to participate in the long-term appreciation of our stockholder value, as well as to share the impact of any business and market setbacks. Unlike many companies in our industry, we have a practice of granting equity-based awards deep in our organization, believing that we will succeed if our employees feel invested in us, our business and our future.

Initial and Promotional Long-Term Incentive Grants:

The size of the initial long-term incentive grant made to executives upon joining the Company or to current employees being promoted to executive positions is primarily based on competitive considerations applicable to the executive’s specific position. In addition, our Compensation Committee considers the number of shares of common stock underlying equity-based awards held by other executives in comparable positions within our Company and has, with the assistance of its independent compensation consultant, established long-term incentive guidelines for specified categories of executives. We believe this strategy is consistent with the approach of other companies in our peer group and, in our Compensation Committee’s view, is appropriate for aligning the interests of our executives with those of our stockholders over the long-term.

Market Comparisons:

We use a number of methodologies to make external comparisons when we determine the number of options, shares of restricted stock and/or performance shares to be granted to each executive. On an individual basis, we compare:

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On a total Company basis, we analyze:

We believe these comparisons provide important additional context for comparing the competitiveness of our equity-based compensation practices versus the market in light of the Company’s own needs and circumstances.

Ultimately, awards to executives are driven by their and our Company’s performance over time, their ability to impact our results that drive stockholder value, their level within the organization, their potential to take on roles of increasing responsibility in our Company, and competitive equity award levels for similar positions in our peer group. Equity-based awards are not granted automatically to our executives on an annual basis.

Certain Awards:

2015 Grants:

In July 2015, our Compensation Committee approved a company-wide performance share grant to all employees at the time, including all of our executives, which are eligible to vest in one-third increments over the three-year period beginning on July 1, 2015 based on the achievement of certain key Company milestones that are significant to the success of our business and the recipient’s continued employment or service with the Company through the vesting date. Our Compensation Committee chose as the milestones what it believed to be key drivers of our business that will help create long-term value for our stockholders. Any portion of each performance share award that does not vest during the applicable year will be forfeited automatically at the end of such year.

In April 2016, one-third of the July 2015 grant vested when we dosed our first patient in our Phase 1 clinical trial for our antibody candidate targeting CTLA-4. In April 2017, an additional one-third of the July 2015 grant vested when we dosed our first patient in our Phase 1/2 clinical trial for our antibody candidate targeting PD-1. In October 2017, the final one-third of the July 2015 grant vested when Incyte dosed its first patient in its INCAGN 1949-201 study, which is a partnered program involving a CPM combination product candidate targeting OX40.

2016 Grants:

On March 31, 2016, as part of a Company-wide award, each of our executives received a grant of stock options, with an exercise price equal to the closing price of our common stock on the date of grant. These options vest as to one-third of the options on the first anniversary of the grant date and thereafter in quarterly installments, generally subject to the recipient’s continued employment or service with the Company. On this same date, our Compensation Committee approved an additional performance share grant to our executives that are eligible to vest (if at all) in a single tranche on March 31, 2019 if upon the 90-day average closing price of our common stock on such date exceeds the thresholds described below, generally subject to the recipient’s continued employment or service with the Company through that date (the “March 2016 Performance Share Grants”). As part of the March 2016 Performance Share Grants, each recipient was granted a target number of performance shares, with any ultimate vesting to be achieved as follows: (i) if the 90-day average closing price is

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less than $10 per share, no portion of the award will vest and the performance share awards will be forfeited in their entirety; (ii) if the 90-day average closing price is equal to $10 per share, 50% of each individual’s target award will vest immediately; (iii) if the 90-day average closing price is equal to $15 per share, 100% of each individual’s target award will vest immediately; (iv) if the 90-day average closing price is $20 per share or greater, 150% of each individual’s target award will vest immediately; and (v) if the 90-day average closing price is between $10 per share and $20 per share, a proportionate number of shares will vest immediately, determined on a straight-line basis. In the event of a change of control of the Company prior to March 31, 2019, the March 2016 Performance Share Grants are subject to vesting solely based upon the per share stock price in the change of control transaction and the above share price targets; if the per share price is less than $10 per share, no portion of the awards will vest and the awards will be forfeited in their entirety. Finally, certain of our executives received supplemental grants of stock options.

2017 Grants:

On March 31, 2017, as part of a Company-wide award, each of our executives received a grant of stock options, with an exercise price equal to the closing price of our common stock on the date of grant. These options vest as to one-third of the options on the first anniversary of the grant date and thereafter in quarterly installments, generally subject to the recipient’s continued employment or service with the Company.

Benefits.

We provide the following benefits to our executives generally on the same basis as the benefits provided to all of our employees:

We believe that these benefits are consistent with those offered by companies against which we compete for talent.

We have also provided personal health-related benefits to our executives from time to time, including certain benefits to Dr. Stein as described in the Summary Compensation Table. In 2017, we also provided Dr. Armen with an allowance to use a private aircraft for business and/or personal travel, we provided Dr. Duncan with a housing allowance, and we provided Dr. Stein with a housing allowance, access to Company housing, and financial planning and advisory services during the time he was an employee and for a brief transition period, all as described below. Consistent with prior years, we provided these benefits to Dr. Stein in order to allow him to focus on his duties as our President of R&D without the disruption associated with having to relocate his home, which we believed, in turn, would increase long-term stockholder value.

Severance Compensation and Termination Protection.

We have employment and change of control agreements with Dr. Armen and Ms. Valentine. Dr. Duncan and Ms. Klaskin participate in our executive change of control plan. These agreements and this plan provide for severance compensation to be paid if the executive’s employment is terminated under certain conditions, such as in connection with a change of control of the Company or a termination without cause by us, each as is defined in the respective agreements or plan. We previously were party to an employment and change of control agreement

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with Dr. Stein. In connection with his retirement, we entered into a severance agreement and a consulting agreement with him. Dr. Stein’s severance agreement and consulting agreement are described below under “Compensation Actions for our Named Executive Officers.”

The employment and change of control agreements and the executive change of control plan, as applicable, between the Company and our executives (other than Dr. Stein and Dr. Cuillerot) and the related severance compensation provisions are designed to meet the following objectives:

Compensation Actions for our Named Executive Officers in 2017

Compensation actions for 2017 reflect our Compensation Committee’s assessments of performance relative to Company goals and objectives and individual performance objectives, and comparisons against the market references described above.

Dr. Armen, our Chief Executive Officer, makes recommendations to our Compensation Committee as to individual compensation actions for our executives, including our named executive officers, but excluding himself. Our Compensation Committee works with our Head of Human Resources and our independent compensation consultant to determine the specific compensation actions for our executives. Our Compensation Committee makes all final determinations regarding the compensation of our executives, including our named executive officers.

Our compensation actions for our Chief Executive Officer and our other named executive officers are summarized as follows:

Dr. Garo H. Armen—Chairman and Chief Executive Officer

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Christine M. Klaskin—Vice President, Finance

Dr. Alexander Duncan—Chief Technology Officer and Head of Research

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Karen H. Valentine—Chief Legal Officer and General Counsel

Dr. Robert B. Stein—Former President, Research & Development (retired April 1, 2017)

Dr. Jean-Marie Cuillerot—Former Chief Medical Officer (employment ended January 17, 2018)

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Tax and Accounting Considerations

Section 162(m) (“Section 162(m)”) of the Internal Revenue Code of 1986, as amended (the “Code”) generally disallows a tax deduction for any publicly-held corporation for individual compensation exceeding $1 million in any taxable year that is paid to certain executive officers of the corporation. For 2017 and prior years, this limitation did not apply to compensation that qualifies as performance-based under Section 162(m). The performance-based compensation exception to Section 162(m) was repealed and certain other changes were made to Section 162(m), generally effective for taxable years beginning after December 31, 2017. As a result, compensation paid to certain current and former executive officers in excess of $1 million in a taxable year generally will not be deductible beginning in 2018 unless such compensation qualifies for transition relief applicable to legally-binding contracts that were in effect on November 2, 2017 or qualifies under a transition rule related to our initial public offering. In making compensation decisions, including those described above, the Compensation Committee considers the tax and accounting implications of its decisions, including limitations on tax deductibility. However, the Compensation Committee believes that its primary responsibility is to provide a compensation program that attracts, retains and rewards the executives necessary for our success. Accordingly, the Compensation Committee may, in its judgment, authorize compensation payments that are not deductible under Section 162(m) or that may otherwise be limited as to tax deductibility. The Compensation Committee has not adopted a policy that compensation must be tax deductible or have the most favorable accounting treatment to the Company.

Our Compensation Committee regularly considers the accounting implications of significant compensation decisions, especially in connection with decisions that relate to our equity incentive award plans and programs. If accounting standards change, we may revise certain programs to appropriately align accounting expenses of our equity awards with our overall executive compensation philosophy and objectives.

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COMPENSATION COMMITTEE REPORT

The Compensation Committee of the Board has reviewed and discussed with management the foregoing Compensation Discussion and Analysis, and based on such review and discussion, the Compensation Committee recommended to the Board that the Compensation Discussion and Analysis be included in this proxy statement on Schedule 14A for filing with the SEC.

By the Compensation Committee,

Wadih Jordan (Chair)

Brian Corvese

Timothy R. Wright

The Compensation Committee of the Board consists entirely of independent directors who are not officers or employees of Agenus. The Compensation Committee charter is posted on the corporate governance section of our website at http://investor.agenusbio.com/board-committees. No material on our website is part of this proxy statement.

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COMPENSATION OF EXECUTIVE OFFICERS

Summary Compensation Table

This table shows certain information about the compensation paid or awarded to, or earned by, our named executive officers for 2017, 2016, and 2015, as applicable.

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Other Compensation

This table shows the components of the “All Other Compensation” received by our named executive officers in 2017.

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Grants of Plan-Based Awards for 2017

This table shows our grants of plan-based awards to our named executive officers in 2017. The awards listed below were all granted under our 2009 Equity Incentive Plan. The exercise price of all stock options granted during 2017 was equal to the closing market price of the Company’s common stock on the date of the grant.

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Outstanding Equity Awards at Fiscal Year-End 2017

The following table shows outstanding equity awards for the named executive officers as of December 31, 2017:

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Option Exercises and Stock Vested for 2017

The following table shows information about performance shares that vested in 2017 and the value realized on those awards by our named executive officers in 2017. No stock options were exercised by our named executive officers in 2017.

Pension Benefits for 2017

We do not have any plans providing for payments or other benefits to our named executive officers at, following, or in connection with, retirement.

Nonqualified Defined Contribution and Other Nonqualified Deferred Compensation Plans for 2017

We do not have any nonqualified defined contribution plans or other deferred compensation plans for our named executive officers.

Potential Payments Upon Termination or Change of Control

We have entered into certain agreements and maintain certain plans that may require us to make certain payments and/or provide certain benefits to our named executive officers in the event of a termination of employment or a change of control. Dr. Armen and Ms. Valentine are each currently party to employment and change of control agreements providing for payments in connection with such executive’s termination of employment or a change of control. Ms. Klaskin and Dr. Duncan are each subject to agreements under our executive change of control plan which provide for payments in connection with such executive’s termination of employment or a change of control. A “change of control” is defined in each of the agreements and plan generally as (i) the acquisition by any individual, entity or group of 50% or more of the common stock of the Company, (ii) a change in the incumbent Board such that incumbent directors cease to constitute at least a majority of our Board, (iii) a sale or other disposition of all or substantially all of the assets of the Company, or (iv) approval by the stockholders of the Company of a complete liquidation or dissolution of the Company. The following text and tables summarize the potential payments to each applicable named executive officer assuming that the triggering event occurred on December 31, 2017, the last day of our fiscal year, unless otherwise noted below.

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Effective April 1, 2017, Dr. Stein retired as President of R&D and became a senior R&D advisor to the Company. The Company and Dr. Stein entered into a severance agreement and a consulting agreement, which superseded the terms of Dr. Stein’s employment and change of control agreement, the severance provisions of which were the same as those described below for Ms. Valentine (other than the gross-up provision contained in Ms. Valentine’s agreement). Pursuant to the severance agreement, the Company paid Dr. Stein $250,000 in a lump sum upon termination and agreed to pay the full premium of Dr. Stein’s participation in the Company’s medical and dental insurance plans for 15 months (the approximate value of these premium payments, based on the premium payments in effect during 2017, is $41,451). Pursuant to the consulting agreement, Dr. Stein is paid a monthly retainer of approximately $35,400. The consulting agreement has an initial term of 15 months, which may be extended by mutual agreement, and can only be terminated by mutual consent or by the Company in the event Dr. Stein breaches the agreement or is unable to perform services for the Company. Dr. Stein’s equity awards will continue to vest during the term of the consulting agreement. In the event there is a change of control of the Company during the term of the consulting agreement, the vesting on all of Dr. Stein’s stock options would be accelerated in full immediately.

Effective January 17, 2018, Dr. Cuillerot’s employment with the Company was terminated. The Company and Dr. Cuillerot entered into a severance agreement which superseded the terms of Dr. Cuillerot’s employment and change of control agreement. Pursuant to the severance agreement, the Company is paying Dr. Cuillerot 75% of his base salary for a 20-week period following termination (for an aggregate amount of severance payments equal to $122,596).

Our Chief Executive Officer

Under Dr. Armen’s employment and change of control agreement, if we terminate Dr. Armen’s employment without cause or if he terminates his employment for good reason (each, as defined in his agreement), he is entitled to receive from the Company:

Under Dr. Armen’s employment and change of control agreement, “good reason” means the occurrence of any of the following events:

Upon a change of control, 100% of any of Dr. Armen’s outstanding unvested performance shares immediately vest (other than the March 2016 Performance Share Grant, which will vest based solely on the per share stock price in the change of control transaction as described above) and 50% of any of Dr. Armen’s outstanding unvested stock options as of the change of control date become vested and exercisable and, in the

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case of shares of restricted stock, no longer subject to forfeiture. If a change of control occurs and, within 24 months, we terminate Dr. Armen’s employment without cause or if he terminates his employment for good reason, he is entitled to receive from the Company:

Additionally, under Dr. Armen’s employment and change of control agreement, he is subject to non-competition and non-solicitation restrictions for the greater of a period of 18 months post-termination or the period during which he is receiving post-termination payments from us.

* We used the following assumptions to calculate these payments:

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Other Named Executive Officers

Under Ms. Valentine’s employment and change of control agreement, if we terminate Ms. Valentine’s employment without cause or if Ms. Valentine terminates her employment following a material reduction in base salary or benefits (“Compensation Reduction”), Ms. Valentine is entitled to receive from the Company:

Under Ms. Valentine’s employment and change of control agreement, upon a change of control:

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Under Ms. Valentine’s employment and change of control agreement, “good reason” means the occurrence of any of the following events:

Under the change of control agreement with Ms. Klaskin, upon a change of control:

Under the change of control agreement with Dr. Duncan, upon a change of control:

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Under the change of control agreement with Ms. Klaskin and Dr. Duncan, “good reason” means: (i) a material reduction in his/her base salary, benefits, duties or responsibilities; or (ii) relocation of his/her principal office, without his/her consent, to a location more than 30 miles away.

Additionally, under Ms. Klaskin’s, Dr. Duncan’s and Ms. Valentine’s agreements, they are each subject to a non-competition and non-solicitation period for the greater of 12 months post-termination or the period during which the officer is receiving post-termination payments from us.

The following table shows the payments that our named executive officers (other than Drs. Armen and Stein) would have been entitled to receive in the event of a termination of employment (i) in connection with a change of control and (ii) without cause or for compensation reduction or with good reason, in each case as of December 31, 2017. Dr. Cuillerot’s employment ended January 17, 2018, and the amount below reflects actual severance paid to Dr. Cuillerot under a post-employment consulting agreement.

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Change of Control Under Our 2009 Equity Incentive Plan

Under our 2009 Equity Incentive Plan, in the event of a change of control (as determined by the Board), the Board may make a provision for the continuation, acceleration or assumption or substitution of unvested options and restricted stock, or provide for a cash-out of outstanding awards.

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DIRECTOR COMPENSATION

The following table shows the compensation paid or awarded to each non-employee director for his or her service as a non-employee director in 2017:

Employee directors do not receive any additional compensation for their service as a director. Each year, the Compensation Committee reviews the compensation we pay to our non-employee directors. The committee compares our Board compensation to compensation paid to non-employee directors by companies in our peer group, described above. The committee also considers the responsibilities that we ask our Board members to assume and the amount of time required to perform those responsibilities.

In March 2017 and in connection with the Company’s restructuring efforts, the Board formed a new committee, called the Executive Committee. Given the departure of certain members of the Company’s senior management team, the Board formed the Executive Committee to act on behalf of the Board more frequently between regularly scheduled Board meetings. Following the formation of the Executive Committee, the Board dissolved the Business Development Advisory Committee in June 2017.

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Cash and Equity Compensation for Non-Employee Directors for 2017

Agenus also reimburses non-employee directors for reasonable travel and out-of-pocket expenses in connection with his or her service as director.

Our Directors’ Deferred Compensation Plan (as amended) (the “DDCP”) permits each non-employee director to defer all or a portion of his or her cash compensation until his or her service ends or until a specified date. A director may credit his or her deferred cash into an interest bearing account, an equity account tied to the value of our common stock, or a combination of both. As a matter of policy, directors are encouraged to elect to defer twenty-five percent of their cash compensation into an equity account under the DDCP.

The Board has adopted a policy guideline that encourages directors to hold 10,000 shares of our common stock within a reasonable period of time following their election or appointment to the Board. In addition to purchasing shares in the open market, directors may utilize the DDCP or the Agenus Board Compensation Policy, which allows directors to receive their compensation in stock, to acquire these shares. In accordance with the requirements of the DDCP, elections to defer compensation thereunder must be made prior to the end of the third quarter of the prior calendar year. In some cases, a director, due to securities law restrictions, may be unable to purchase such shares until such election takes effect.

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Chief Executive Officer Pay Ratio

As required by Section 953(b) of the Dodd-Frank Wall Street Reform and Consumer Protection Act, and Item 402(u) of Regulation S-K, we are providing the following information regarding the ratio of total annual compensation for Dr. Armen, our chairman and chief executive officer (the “CEO”), to the median of the annual total compensation of all our employees (other than the CEO). For 2017:

In determining the median employee, we chose December 31, 2017 as the date to identify our median employee, and we identified our median employee using the consistently applied compensation measure of 2017 Box 1 W-2 wages. In making this determination, we annualized the compensation of all employees who were hired in 2017 and were working for us on December 31, 2017, but who did not work for us the entire fiscal year. After we identified our median employee, we measured the employee’s annual total compensation under SEC rules using base salary earned in 2017, annual cash bonus paid in March 2018 for the 2017 performance year, the grant date value of any equity awards received in 2017 and the 401(k) match provided by the Company in 2017, in each case, if applicable. We calculated our median employee’s total annual compensation using the same methodology we used to calculate Dr. Armen’s annual total compensation, as reflected in the “Total” column of the Summary Compensation table above.

This pay ratio is a reasonable estimate calculated in a manner consistent with SEC rules based on our records and the methodology described above. The SEC rules for identifying the median compensated employee and calculating the pay ratio based on that employee’s annual total compensation allow companies to adopt a variety of methodologies, to apply certain exclusions, and to make reasonable estimates and assumptions that reflect their compensation practices. As such, the pay ratio reported by other companies may not be comparable to the pay ratio reported above.

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OWNERSHIP OF OUR COMMON STOCK

Ownership By Management

On April 24, 2018, Agenus had 103,999,081 shares of common stock issued and outstanding. The table below shows certain information about the beneficial ownership of Agenus common stock, as of April 24, 2018, by:

In accordance with SEC rules, we have included in the column “Number of Issued Shares” all shares of common stock over which the person has sole or shared voting or investment power as of April 24, 2018, and we have included in the column “Number of Shares Issuable” all shares of common stock that the person has the right to acquire within 60 days after April 24, 2018 through the exercise of any stock options, the vesting of restricted shares, or in the case of directors, any shares to be distributed under the DDCP. All shares that a person has a right to acquire within 60 days of April 24, 2018 are deemed outstanding for the purpose of computing the percentage beneficially owned by the person, but are not deemed outstanding for the purpose of computing the percentage beneficially owned by any other person

Unless otherwise indicated, each person has the sole power (or shares the power with a spouse) to invest and vote the shares of common stock listed opposite the person’s name. Where applicable, ownership is subject to community property laws. Our inclusion of shares in this table as beneficially owned is not an admission of beneficial ownership of those shares by the person listed in the table. Except as noted, the address of each stockholder is c/o Agenus Inc., 3 Forbes Road, Lexington, Massachusetts 02421.

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Ownership By Certain Beneficial Owners

This table shows certain information, based on filings with the SEC, about the beneficial ownership of our capital stock as of April 24, 2018 by each person known to us owning beneficially more than 5% of any class of our capital stock. Unless otherwise indicated in a footnote to this table, each person has the sole power to invest and vote the shares of common stock listed opposite the person’s name.