UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

PROXY STATEMENT PURSUANT TO SECTION 14(A)Proxy Statement Pursuant to Section 14(a)

OF THE SECURITIES EXCHANGE ACT OFof the Securities Exchange Act of 1934 (Amendment No.)

Filed by the Registrant  ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

ALTAIR ENGINEERING INC.

(Name of Registrant as Specified In Its Charter)

(Name(s)(Name of Person(s) Filing Proxy Statement, if Other Thanother than the Registrant)

Payment of Filing Fee (Check the appropriate box)all boxes that apply):

ALTAIR ENGINEERING INC.

1820 East Big Beaver Road

Troy, Michigan 48083

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To be held on May 14, 201911, 2022

To the Stockholders of

Altair Engineering Inc.

NOTICE IS HEREBY GIVENthatYou are cordially invited to attend the Annual Meeting of Stockholders (the “Annual Meeting”) of Altair Engineering Inc. (the “Company”) willto be held on Wednesday, May 11, 2022 at the offices of the Company, 1820 East Big Beaver Road, Troy, Michigan 48083, on May 14, 2019, beginning at 9:10:00 a.m. local time.Eastern Time. We are planning to hold the Annual Meeting virtually via the Internet at www.virtualshareholdermeeting.com/ALTR2022. You will not be able to attend the Annual Meeting at a physical location. At the Annual Meeting, stockholders will act on the following matters:

Only stockholders of record at the close of business on March 19, 201916, 2022 are entitled to receive notice of and to vote at the Annual Meeting or any postponement or adjournment thereof.

Your vote is important. Whether or not you plan to attend the meeting, please vote electronically via the Internet or by telephone, or, if you requested paper copies of the proxy materials, please complete, sign, date and return the accompanying proxy card or voting instruction card in the enclosed postage-paid envelope. If you attend the meeting and prefer to vote in person, you may do so even if you have already voted your shares. You may revoke your proxy in the manner described in the proxy statement at any time before it has been voted at the meeting.

By Order of the Board of Directors

April 4, 2019/s/ James R. Scapa

James R. Scapa

Chairman and Chief Executive Officer

March 30, 2022

Troy, Michigan

TABLE OF CONTENTS

ALTAIR ENGINEERING INC.

PROXY STATEMENT

FOR THE 20192022 ANNUAL MEETING OF STOCKHOLDERS

GENERAL INFORMATION

This proxy statement contains information related to the Annual Meeting of Stockholders to be held on Wednesday, May 14, 201911, 2022 at 9:10:00 a.m. local time, at Altair’s offices, 1820 East Big Beaver Road, Troy, Michigan 48083,Eastern Time. We are planning to hold the Annual Meeting virtually via the Internet, or at such other time and place to which the Annual Meeting may be adjourned or postponed. The enclosedIn order to attend our Annual Meeting, you must log in to www.virtualshareholdermeeting.com/ALTR2022 using the 16-digit control number on the Notice, proxy iscard or voting instruction form that accompanied the proxy materials.

Proxies for the Annual Meeting are being solicited by Altair’s Board of Directors (the “Board”). This proxy statement is first being made available to stockholders on or about April 4, 2019.March 30, 2022.

Important Notice of Availability of Proxy Materials for the Annual Meeting of Stockholders to be held on May 14, 2019.11, 2022.

Our proxy materials including our Notice of Internet Availability of Proxy Materials, Proxy Statement for the 20192022 Annual Meeting, our annual report for the fiscal year ended December 31, 20182021 and proxy card are available on the Internet at www.proxyvote.com.UnderSecurities and Exchange Commission rules, we are providing access to our proxy materials by notifying you of the availability of our proxy materials on the Internet.

In this Proxy Statement, the terms “Altair,” “we,” “us,” and “our” refer to Altair Engineering Inc. The mailing address of our principal executive offices is Altair Engineering Inc., 1820 East Big Beaver Road, Troy, Michigan 48083.

About the Meeting

Why are we calling this Annual Meeting?

We are calling the Annual Meeting to seek the approval of our stockholders:

What are the Board’s recommendations?

Our Board believes that the election of the director nominees identified herein and the appointment of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 20192022 are advisable and in the best interests of Altair and its stockholders and recommends that you voteFOR these proposals. Our Board believes that an annual vote, on an advisory basis, on conducting an advisory vote on Named Executive Officerthe compensation is advisable andof our named executive officers for the year ended December 31, 2021, as described in the best interests of Altair and its stockholdersthis proxy statement, was appropriate and recommends that you voteFORone year for this proposal. the resolution to approve that compensation. If you are a stockholder of record and you return a properly executed proxy card or vote by proxy over the Internet but do not mark the boxes showing how you wish to vote, your shares will be voted in accordance with the recommendations of the Board, as set forth above. With respect to any other matter that properly comes before our Annual Meeting, the proxy holders will vote as recommended by the Board or, if no recommendation is given, at their own discretion.

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Who is entitled to vote at the meeting?

Only holders of record of our Class A common stock and Class B common stock at the close of business on the record date, March 19, 2019,16, 2022, are entitled to receive notice of the Annual Meeting and to vote either class of

about April 4, 2019,March 30, 2022, we will begin mailing a Notice of Internet Availability of Proxy Materials (the “Notice”) to all stockholders of record on our books at the close of business on the record date and will post our proxy materials on the website referenced above.at www.proxyvote.com. Stockholders may choose to access our proxy materials on the website referred to aboveat www.proxyvote.com or may request to receive a printed set of our proxy materials. In addition, the Notice and that website provide information regarding how you may request to receive proxy materials in printed form by mail, or electronically by email, on an ongoing basis.

You may vote on the Internet, by telephone, by mail or by attending the Annual Meeting and voting by ballot,electronically, all as described below. The Internet and telephone voting procedures are designed to authenticate stockholders by use of a control number and to allow you to confirm that your instructions have been properly recorded. If you vote by telephone or on the Internet, you do not need to return your proxy card or voting instruction card. Telephone and Internet voting facilities are available now and will be available 24 hours a day until 11:59 p.m., Eastern Time, on May 13, 2019.

Even if you plan to theattend our Annual Meeting remotely, we recommend that you also submit your proxy as described above so that your vote will be counted if you later decide not to obtain this proxy from the holder of record.attend our Annual Meeting.

The shares voted electronically, telephonically, or represented by the proxy cards received, properly marked, dated, signed and not revoked, will be voted at the Annual Meeting.

What if I vote and then change my mind?

You may revoke your proxy at any time before it is exercised by:

Your latest vote will be the vote that is counted.

With respect to the second and third proposals, to vote oncast an advisory basis on the frequency of the advisory votesvote on executive compensation and to ratify the appointment of Ernst & Young LLP, respectively, and the approval of any other matter that may properly come before the Annual Meeting, the affirmative vote of a majority of the voting power of the shares of our common stock present in person or represented by proxy and entitled to vote, is required to approve these proposals. As a result, abstentions will have the same practical effect as a negative vote on these proposals, and “brokernon-votes” (see below), if any, will not affect the outcome of the vote on these proposals.

Holders of the common stock will not have any dissenters’ rights of appraisal in connection with any of the matters to be voted on at the meeting.

What are “brokernon-votes”?

Banks and brokers acting as nominees are permitted to use discretionary voting authority to vote proxies for proposals that are deemed “routine” by the New York Stock Exchange, but are not permitted to use discretionary voting authority to vote proxies for proposals that are deemed“non-routine” by the New York Stock Exchange.

PROPOSAL 1: TO ELECT TWOTHREE DIRECTORS, AS CLASS II DIRECTORS, TO SERVE A THREE-YEAR TERMSTERM EXPIRING AT THE ANNUAL MEETING IN 20222025 AND UNTIL THEIR SUCCESSORS HAVE BEEN DULY ELECTED AND QUALIFIED

Our Board is divided into three classes: Class I, Class II and Class III, with each class serving a three-year term. Vacancies on the Board may be filled only by persons elected by a majority of the remaining directors. A director elected by the Board to fill a vacancy in a class, including vacancies created by an increase in the number of directors, shall serve for the remainder of the full term of that class and until the director’s successor is duly elected and qualified.

TheOur Board presently has seven members. There are twothree directors in the class (Class II) whose term of office expires in 2019. Both2022. Each of these directors havehas been nominated for election as Class II directors at this Annual Meeting. Each of the nominees listed below is currently a director of Altair. If elected at the Annual Meeting, the Class II nominees would serve until the 20222025 annual meeting and until his or her successor has been duly elected and qualified, or, if sooner, until the director’s death, resignation or removal.

Directors are elected by a plurality of the votes of the holders of shares present in person or represented by proxy and entitled to vote on the election of directors. Stockholders may not vote, or submit a proxy, for a greater number of nominees than the twothree nominees named below. The two director nominees receiving the highest number of affirmative votes will be elected. SharesUnless otherwise directed, shares represented by executed proxies will be voted if authority to do so is not withheld, for the election of the two director nominees named below. If any director nominee becomes unavailable for election as a result of an unexpected occurrence, shares that would have been voted for that nominee will instead will be voted for the election of a substitute nominee proposed by our Board. Each person nominated for election has agreed to serve if elected. Our management has no reason to believe that any nominee will be unable to serve.

Class II Nominees for Election for a Term Expiring at the 20222025 Annual Meeting

The following table sets forth the name, age, position and tenure of our Class II directors who are up forre-election election at the 20192022 Annual Meeting for a term expiring at the 20222025 Annual Meeting:

The following biographical descriptions set forth certain information with respect to the director nominees, based on information furnished to Altair by each director nominee.

Trace Harris has served as a member of our board of directorsBoard since August 2016. Ms. Harris is the chair of our compensation committee, a role she has heldsince January 2017, and a member of our audit committee, a role she has held since August 2018. She also served as a member of our nominating and corporate governance committee from April 2017 through August 2018. Ms. Harris currently isserves as a director on the boards of Ziff Davis, Inc., a digital media and internet company (Nasdaq: ZD); Anzu Special Acquisition Corp. I (Nasdaq: ANZUU), a special purpose acquisition company focused on transformative technologies for industrial applications; Bungie, LLC, the video game developer of Halo and Destiny; and USA Climbing, the national governing board of the sport of competition climbing. Ms. Harris currently serves as principal at T Harrisof T-Harris, LLC, which provides strategya media and financialeducation consulting firm, a positionrole she has held since November 2014. Prior to that, she worked atMs. Harris also served as the Chief Financial Officer of A-List Services, LLC, an educational services provider, from January 2017 through Januaryto 2019, most recentlyand during which she served as interim chief executive officer and chief financial officer.acting Chief Executive Officer for a portion of that time. Prior to that, Ms. Harris spent 13 years between September 2001 and November 2014, working in various roles at

Vivendi SA,S.A., most recently serving as senior vice president, strategy, financeSenior Vice President—Strategy, Finance and business innovation.Business Innovation. She was previously Senior Vice President of Strategic Development for Universal Studios Television Group, where

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she was responsible for international television strategies and launched its first international television network. Prior to Universal Studios, Ms. Harris was Director of Finance and Channel Operations for Warner Bros. International Channels. She began her career at JP Morgan in New York. Ms. Harris holds a bachelor’s degree in economics from Stanford University and a master’s degree in business administration with a concentration in finance from the Yale School of Management. We believe Ms. Harris is qualified to serve on our board of directors because of her significant corporate finance, operational and business experience.

Continuing Directors

The following table sets forth the name, age, position and tenure of the directors who are serving for terms that end following the Annual Meeting.

The following biographical descriptions set forth certain information with respect to directors who are serving for terms that end following the Annual Meeting, based on information furnished to Altair by each director.

Class III Directors Continuing in Office until the 2023 Annual Meeting

James R. Scapa co-founded our company and has served as Chairman of our Board and our Chief Executive Officer since 1992. Prior to his role asour Chief Executive Officer, Mr. Scapa served as secretary and treasurer since our inception in 1985. Mr. Scapa holds a bachelor’s degree in mechanical engineering from Columbia University and a masters of business administration degree from the University of Michigan. We believe that the perspective and experience that Mr. Scapa brings as our Chief Executive Officer and founder uniquely qualifies him to serve as the Chairman of our Board. Mr. Scapa is the father of Stephanie Buckner, who became an executive officer of our company in 2021.

Stephen Earhart has served as a member of our Board since May 2011. Mr. Earhart is the chair of our audit committee, a position he has held sinceJanuary 2016, and a member of our compensation committee, a position he has held since January 2015. Mr. Earhart served as Chief Financial Officer of World Kitchen, LLC, a branded consumer products company, from April 2012 to January 2017. From December 2007 to June 2010, Mr. Earhart served as Chief Financial Officer of Torex Retail Holdings, Ltd., a retail software provider based in the United Kingdom. From 2003 to 2007, Mr. Earhart served as the Chief Financial Officer of SSA Global Technologies Inc. (formerly Nasdaq: SSAG) and Infor Global Solutions, each an enterprise resource planning software company. In 2003, Mr. Earhart retired from Motorola, Inc., a telecommunications company, as Senior Vice President of Finance. Mr. Earhart is a certified public accountant and holds a bachelor’s degree in business and accounting from the University of Illinois and a master’s degree in business administration from the University of Wisconsin. We believe Mr. Earhart is qualified to serve on our board of directors because of his significant corporate finance, operational and business experience gained from holding senior executive positions at both publicly-traded and private technology and consumer companies.

Class I Directors Continuing in Office until the 20212024 Annual Meeting

Dr. Mary C. Boycehas served as a member of our board of directorsBoard since April 2018. Dr. Boyce is the chair of our technology committee, a role shehas held since October 2018, and a member of our nominating and corporate governance committee, a role she has held since August 2018. Dr. Boyce is Provost of Columbia University in the City of New York, where she was also Dean of The Fu Foundation School of Engineering and Applied Science at Columbia University in the City of New York, where she is alsoand the Morris A. and Alma Schapiro Professor of Engineering. Prior to joining Columbia University in 2013, Dr. Boyce served on the faculty of the Massachusetts Institute of Technology (“MIT”) for over 25 years, leading the Mechanical Engineering Department from 2008 to 2013. She holds a BS degree in engineering science and mechanics from Virginia Tech, and MS and PhDPh.D. degrees in mechanical engineering from MIT. Dr. Boyce’s research focuses on materials and mechanics, particularly in the areas of multi-scale and nonlinear mechanics of

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polymers and soft composites, and her work has been documented in over 170 archival journal articles spanning materials, mechanics, and physics. She has mentored over 40 M.S. thesis students and over 25 Ph.D. students and has been widely recognized for her scholarly contributions, including election as a fellow of the American Society of Mechanical Engineers, the American Academy of Arts and Sciences, and the National Academy of

CORPORATE GOVERNANCE MATTERS

Board of Director Composition

Our Board currently consists of seven members. Our directors hold office until their successors have been elected and qualified or until the earlier of their resignation or removal.

We have no formal policy regarding board diversity. Our priority in selection of board members is identification of members who will further the interests of our stockholders through his or her established record of professional accomplishment, the ability to contribute positively to the collaborative culture among board members, knowledge of our business and understanding of the competitive landscape.

Board of Director Meetings

Our Board met ten6 times in 2018.2021. Each director attended at least 75% of the aggregate of (i) the total number of meetings of our Board (held during the period for which such director served on the Board) and (ii) the total number of meetings of all committees of our Board on which such director served (during the periods for which the director served on such committee or committees). This is our second Annual Meeting of Stockholders since our initial public offering on October 31, 2017. Altair does not have a formal policy requiring members of the Board to attend our annual meetings. SevenAll directors who were members of our Board at the time, attended the 20182021 annual meeting of stockholders.stockholders, which was held remotely.

Director Independence

Because Mr. Scapa controls a majority of our outstanding voting power, we qualify as a “controlled company” under the corporate governance rules of the NASDAQ Stock Market LLC, or NASDAQ. Therefore, we are not required to have a majority of our Board be independent, nor are we required to have an independent compensation committee or an independent nominating function. Notwithstanding our “controlled company” status, we intend to comply with the majority independence and independent compensation committee and nominating function requirements. Regardless of whether we qualify as a “controlled company”, we are required to have a fully independent audit committee subject to certain transition rules. Additionally, audit committee members must also satisfy the independence criteria set forth in Rule10A-3 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

Under the rules of the Nasdaq Global Select Market, a director will only qualify as an “independent director” if, in the opinion of that company’s board of directors, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In order to be independent, compensation committee members must not have a relationship with the issuer that is material to the director’s ability to be independent from management in connection with the duties of a compensation committee member.

In order to be considered independent for purposes of Rule10A-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 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.

Our Board has undertaken a review of the independence of each director. Based on information provided by each director concerning his or her background, employment and affiliations, our Board determined that Messrs. Anderson, Ayyar and Earhart, Hart and KowalMses. Carter and Ms. Harris, and Dr. Boyce do not have 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 applicable rules and regulations of the Securities and Exchange

Select Market. In making these determinations, our Board considered the current and prior relationships that eachnon-employee director has with our company and all other facts and circumstances our Board deemed relevant in determining their independence, including the beneficial ownership of our capital stock by eachnon-employee director, and any transactions involving them described in the section entitled “Transactions“Transactions with Related Persons.Persons.”

Board Committees

Audit Committee

Our audit committee currently consists of Messrs. Earhart, as chair, and HartAyyar and Ms.Mses. Carter and Harris, each of whom is “independent” as that term is defined under applicable SEC rules and NASDAQ listing standards. Our Board has determined that Mr. Earhart qualifies as an audit committee financial expert within the meaning of SEC regulations and The NASDAQ Marketplace Rules. In making this determination, our Board has considered the formal education and nature and scope of his previous experience, coupled with past and present service on various audit committees. Our audit committee assists our Board in its oversight of our accounting and financial reporting process and the audits of our financial statements.

Our audit committee’s responsibilities include:

All audit services to be provided to us and allnon-audit services to be provided to us by our independent registered public accounting firm must be approved in advance by our audit committee.

Our audit committee operates pursuant to a charter that is available on our website at www.investor.altair.comhttp://investor.altair.com under the Governance section. Our audit committee met nine10 times in 2018.2021.

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Compensation Committee

Our compensation committee currently consists of Ms. Harris, as chair, and Messrs. EarhartAnderson and Kowal,Earhart, each of whom is “independent” as that term is defined under applicable SEC rules and NASDAQ listing

Our technology committee operates pursuant to a charter. It met once3 times in 2018; it was formed in August, 2018.2021.

Stockholder Nominations for Directorships

Our nominating and corporate governance committee will consider potential director candidates recommended by stockholders as long as the stockholders comply with our certificate of incorporation and bylaws, in recommending a potential candidate. Stockholders who wish to recommend a candidate for nomination should contact our corporate secretary in writing and provide the following information:

Assuming that appropriate information is provided for candidates recommended by stockholders on a timely basis, our nominating and corporate governance committee will evaluate those candidates by following substantially the same process, and applying substantially the same criteria, as for candidates submitted by members of the Board or other persons, as described above and as set forth in its charter.

Board Diversity

The following Board Diversity Matrix presents our Board diversity statistics in accordance with Nasdaq Rule 5606. The information is based on our directors’ self-reporting and reflects compliance with the objectives of Nasdaq Rule 5605(f)(3) by having at least one director who identifies as female and at least one director who identifies as a member of an Underrepresented Minority (as defined by Nasdaq Rules). As we pursue future Board recruitment efforts, our Nominating and Corporate Governance Committee will continue to seek candidates who can contribute to the diversity of views and perspectives of the Board. This includes seeking out individuals of diverse ethnicities, a balance in terms of gender, and individuals with diverse perspectives informed by other personal and professional experiences.

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Board Leadership Structure and Role in Risk Oversight

The chief executive officer and Chairman positions are held by James Scapa. Mr. Scapa also beneficially owns approximately 52%52.3% of the voting power of our common stock. Periodically, our Board assesses these roles and the Board leadership structure to ensure the interests of Altair and our stockholders are best served. Our Board has determined that its current leadership structure is appropriate. James Scapa, as one of our founders and as our chief executive officer and Chairman, has extensive knowledge of all aspects of Altair, our business and risks, and our customers. Our Board has no Lead Independent Director; however, the Board may choose to elect one.

While management is responsible for assessing and managing risks to Altair, our Board is responsible for overseeing management’s efforts to assess and manage risk. This oversight is conducted primarily by our full Board, which has responsibility for general oversight of risks, and our standing Board committees. Our Board satisfies this responsibility through full reports by each committee chair regarding the committee’s considerations

Communications from stockholders will be forwarded to all directors if they relate to important substantive matters or if they include suggestions or comments that the Secretary considers to be important for the Board to know. Communication relating to corporate governance and corporate strategy are more likely to be forwarded to the Board than communications regarding personal grievances, ordinary business matters, and matters as to which Altair tends to receive repetitive or duplicative communications.

Stockholders who wish to send communications to the Board should address such communications to: The Board of Directors, Altair Engineering Inc., 1460 Broadway, New York, New York 10036,1820 East Big Beaver Road, Troy, Michigan 48083, Attention: Secretary.

Code of Business Conduct and Ethics

We maintain a written code of business conduct and ethics that applies to our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. A current copy of the code is posted on the Governance section of our website, which is located at www.investor.altair.com.http://investor.altair.com. If we make any substantive amendments to, or grant any waivers from, the code of business conduct and ethics for any officer or director, we will disclose the nature of such amendment or waiver on our website or in a current report on Form8-K.

Compensation Committee Interlocks and Insider Participation

Our compensation committee currently consists of Ms. Harris, as chair, and Messrs. EarhartAnderson and Kowal.Earhart. No member of our compensation committee is or has been an officer or employee of Altair. None of our executive officers currently serves, or during fiscal 20182021 has served, as a member of the compensation committee or director (or other board committee performing equivalent functions or, in the absence of any such committee, the entire board of directors) of any entity that has one or more executive officers serving on our compensation committee or our Board.

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EXECUTIVE OFFICERS

The following table sets forth certain information regarding our current executive officers:

Our executive officers are elected by, and serve at the discretion of, our Board. The business experience for the past five years, and in some instances, for prior years, of each of our executive officers is as follows:

James R. Scapahas served as our chief executive officerChief Executive Officer since 1992. For Mr. Scapa’s biography, please see the section above entitled “Class III DirectorsNominees Continuing in Office until the 20202023 Annual Meeting.”

Brett ChouinardMatthew Brown has served as our PresidentChief Financial Officer since March 16, 2021, after serving as one of our Senior Vice Presidents-Finance since January 1, 2018. For2021. Prior to joining our company, Mr. Chouinard’s biography, please seeBrown served in Finance leadership roles at NortonLifeLock, a leading consumer cyber safety company, including as Interim Chief Financial Officer from November 2019 to July 2020. Prior to that, he served in Finance leadership roles at Symantec, a leading provider of enterprise security software, from August 2016 to November 2019, most recently as Vice President of Finance and Chief Accounting Officer. Prior to that, Mr. Brown served as Vice President, Controller for Blue Coat Systems, a provider of advanced web security solutions, from October 2015 to August 2016. Prior to that, Mr. Brown served in various Finance roles at NETGEAR (2010 to 2015) and Brocade Communications (2008 to 2010). He began his career at KPMG, LLP. Mr. Brown is a certified public accountant and holds a Bachelor of Science degree in business administration from the section above entitled “Class I Directors Continuing in Office untilWalter A. Haas School of Business at the 2021 Annual Meeting.”University of California, Berkeley.

Howard N. MorofStephanie Buckner has served as our chief financial officerChief Operating Officer since February 2013.January 1, 2022 and is responsible for our corporate development efforts and field operations, sales and technical support globally. Prior to this role, Ms. Buckner served as our Senior Vice President of Customer Engagement and Corporate Development from January 2021 to January 2022. Prior tothis role, Ms. Buckner served as our senior vice president of corporate development from January 2019 to January 2021. Ms. Buckner joined Altair in June 2011 as a partner solutions manager. Ms. Buckner holds a bachelor’s degree in industrial and operations engineering from the University of Michigan. Ms. Buckner is the daughter of James Scapa, our founder, Chairman and Chief Executive Officer.

Brett Chouinard has served as our Chief Product and Strategy Officer since January 1, 2022, after serving as our Chief Technology Officer of modeling and visualization since June 2021. Prior to that, Mr. Morof alsoChouinard served as our President from January 1, 2018 to June 2021 and a member of our board of directors from February 2011January 1, 2018 until the 2021 annual meeting of stockholders. Prior to February 2013.these roles, Mr. Chouinard served as our ChiefOperating Officer, a position he held from January 2010 to June 2021. Prior to his role as our chief operating officer, Mr. Chouinard

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served in various roles with us since 1994. Prior to joining us, Mr. Morof servedChouinard worked as chief financial officeran engineer at GE Aircraft, a subsidiary of North American Bancard, LLC, an independent merchant and credit card processing company, from February 2008 to February 2013.General Electric, Inc. specializing in aircraft engines. Mr. Morof is a certified public accountant and holds a master’s degree in taxation from Walsh College and a bachelor’s degree in business administration from the University of Michigan.

James P. Dagg has served as our chief technical officer of modeling and visualization since January 2014. Prior to this role, Mr. Dagg served from May 2008 to December 2013 as the vice president of our wholly-owned subsidiary solidThinking, Inc. Mr. DaggChouinard holds a bachelor’s degree in mechanical engineering from Michigan Technological University and a master’s degree in applied mechanicsmechanical engineering from the University of Michigan.Cincinnati.

Dr. Uwe Schrammhas served as our chief technical officerChief Visionary Officer since January 1, 2022, after serving as our Chief Technical Officer of solvers and optimization since January 2014. Prior to this role, Dr. Schrammserved as managing director of Altair GmbH, our wholly-owned German subsidiary, from September 2011 to December 2013. Prior to his role as managing director, Mr. Schramm served in various roles with us since 1996. Dr. Schramm holds a master’s degree and a doctorate degree in solid mechanics from the University of Rostock in Rostock, Germany.

Mahalingam Srikanthhas served as our chief technicalChief Technology officer since January 1, 2022, after serving as our Chief Technical Officer for HPC and cloud solutions since January 2014. Prior to this role, Mr. Srikanthwas a senior vice president at Altair from July 2011 to November 2013 and a vice president at Altair from January 2008 to June 2011. Mr. Srikanth holds a bachelor’s degree in computer science and engineering from Gulbarga University in Gulbarga, India and an executive masters of business administration from the Indian School of Business in Hyderabad, India.

Nelson Diashas served as our chief revenue officerChief Revenue Officer since January 1, 2018, after serving as our Senior VP—Asia Pacific since 2006. Prior torunning Altair’s APAC region, Mr. Dias was Managing Director of Altair India from 2002-2005. He has over 28 years of technical sales and management experience. Mr. Dias holds a Bachelor of Engineering in Computer Science degree from the University of Mumbai.

Brian Gayle has served as our Senior Vice President, Chief Accounting Officer since September 2018 and also became our principal accountingofficer in March 2021. From March 2015 to September 2018, Mr. Gayle served as our Vice President-Corporate Controller. Prior to these roles, Mr. Gayle began his career at Deloitte & Touche, LLP. Mr. Gayle is a certified public accountant and holds a Bachelor’s degree of Accountancy from Walsh College.

Jeff Marraccini has served as our Chief Information Security Officer since February 2022. Previously, he served as our Senior Vice President of Cloud Strategy & Technology from May 2021 to February 2022 and our Senior Vice President of IT Strategy & Technology from April 2021 to May 2021. Prior to that, Mr. Marraccini served as our Senior Vice President of Global IT Systems from October 2018 to May 2021. From January 2011 to October 2018, Mr. Marraccini served as our Vice President of Computer Systems. Mr. Marraccini holds a bachelor’s degree in economics, computer science, and anthropology from Oakland University.

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EXECUTIVE COMPENSATION

Compensation Discussion and Analysis

Introduction

This Compensation Discussion and Analysis provides information regarding the 20182021 compensation program for our principal executive officer, our principal financial officer and the three other most highly-compensated executive officers (our “Named Executive Officers”). For 2018,2021, our Named Executive Officers were:

Mr. Morof was our CFO until March 16, 2021. At the close of business on March 16, 2021, Mr. Brown became our CFO.

This Compensation Discussion and Analysis describes the material elements of our executive compensation program during 2018.2021. It also provides an overview of our executive compensation philosophy, including our principal compensation policies and practices. Finally, it analyzes how and why the Compensation Committee of our Board of Directors (the “Compensation Committee”) arrived at the specific compensation decisions for our Named Executive Officers in 2018,2021, and discusses the key factors that the Compensation Committee considered in determining their compensation.

We believe a critical component of our success has been our company culture, based on our core values of innovation, envisioning the future, communicating honestly and broadly, seeking technology and business firsts, and embracing diversity. This culture is important because it helps attract and retain top people, encourages innovation and teamwork, and enhances our focus on achieving our corporate objectives.

20182021 Business Results

20182021 was a strong year for us, reflecting both improved executioncontinuing growth of our software platforms and progressintegration of important acquired technologies as we continue to growconfronted the Company.business and personal safety challenges imposed by COVID-19. In 2018, we achieved significant results, including:2021:

A reconciliation of the GAAP andnon-GAAP information referenced above is set forth in Appendix A to this Proxy Statement.

As discussed Our compensation determinations for 2021 were based, in our Annual Report on Form10-K for the year ended December 31, 2018 filed on March 1, 2019, we were required to adopt ASC 606 governing revenue recognition as of January 1, 2018. We encourage stockholders to review our Annual Report for a discussion of the impact of the adoption of ASC 606part, on our reported results.2021 performance.

Pay-for-Performance

We believe our executive compensation program is reasonable, competitive, and appropriately balances the goals of attracting, motivating, rewarding, and retaining our executive officers with the goal of aligning their interests with those of our stockholders. To foster this alignment and to motivate and reward individual initiative and effort, a portion of our executive officers’ target annual total direct compensation opportunity is both performance-based and“at-risk.”

We emphasize variable compensation that appropriately rewards our executive officers, including our Named Executive Officers, through two separate compensation elements:

These variable pay elements assure that a meaningful portion of our executive officers’ target total direct compensation is contingent (rather than fixed) in nature, with the amounts ultimately payable subject to variability above or below target levels commensurate with our actual performance.

We believe that this design provides balanced incentives for our executive officers to drive financial performance and long-term growth.

Executive Compensation Policies and Practices

We endeavor to maintain sound governance standards in the design and implementation of our executive compensation policies and practices. The Compensation Committee evaluates our executive compensation program on a regular basis to ensure that it is consistent with our short-term and long-term goals, given the dynamic nature of our business and the market in which we compete for executive talent. The following summarizes our executive compensation and related policies and practices:

What We Do

Stockholder Advisory Votes on Named Executive Officer Compensation

Commencing with next year’s annual meeting of stockholders, we willWe are required to conduct anon-binding stockholder votevotes on the compensation of our Named Executive Officers (commonly known asa “Say-on-Pay”“Say-on-Pay” vote). At this year’sour 2019 annual meeting of stockholders, we will conductconducted anon-binding stockholder vote on the frequency of futureSay-on-Pay votes (commonly known as a“Say-When-on-Pay” vote). We have recommended that such votes be conducted annually.annually and our stockholders overwhelmingly approved that recommendation. We will hold a Say-on-Pay vote at each annual meeting until the time our stockholders vote to hold the Say-on-Pay vote at a different frequency. See Proposal 2 in this Proxy Statement.

At the 2021 Annual Meeting, approximately 99% of the votes cast in connection with the stockholders advisory vote on compensation of the NEOs were cast in favor of the proposal. We value the opinions of our stockholders. Ourstockholders We have considered this voting result, and our Board of Directors and the Compensation Committee will consider the outcome ofSay-on-Pay votes, as well as feedback received throughout the year, when making compensation decisions for our executive officers, including our Named Executive Officers.

Executive Compensation Philosophy and Objectives

Our executive compensation program is guided by our overarching philosophy of paying for demonstrable performance. Consistent with this philosophy, we have designed our executive compensation program to achieve the following primary objectives:

In addition, we have not adopted policies or employed guidelines for allocating compensation between current and long-term compensation, between cash andnon-cash compensation, or among different forms ofnon-cash compensation.

Compensation-Setting Process

Role of the Compensation Committee

The Compensation Committee discharges the responsibilities of our Board of Directors relating to the compensation of our CEO and oversight of compensation matters for our Named Executive Officers, and recommends for Board of Director approval compensation for thenon-employee members of our Board of Directors.TheDirectors. The Compensation Committee has overall responsibility for overseeing our compensation and benefits policies generally, and overseeing and evaluating the compensation plans, policies, and practices applicable to our CEO and other executive officers. In addition, the Compensation Committee makes all final decisions regarding the compensation of our CEO and other executive officers. The Compensation Committee is also responsible for the administration of our 2021 Employee Stock Purchase Plan (the “ESPP”), in which employees participate on a voluntary basis.

In carrying out its responsibilities, the Compensation Committee evaluates our compensation policies and practices with a focus on the degree to which these policies and practices reflect our executive compensation philosophy, develops strategies and makes recommendations that it believes further our philosophy or align with developments in best compensation practices.

The Compensation Committee’s authority, duties, and responsibilities are further described in its charter, which is reviewed annually and revised and updated as warranted. The charter is available on our website at www.investor.altair.com.http://investor.altair.com.

The Compensation Committee retains a compensation consultant (as described below) to provide support in its review and assessment of executive compensation.compensation as needed.

Setting Target Total Direct Compensation

The Compensation Committee reviews the base salary levels, annual incentive bonus payments and long-term incentive compensation opportunities of our executive officers, including our Named Executive Officers, and related performance criteria.

The Compensation Committee does not establish a specific target for formulating the target total direct compensation opportunities of our executive officers. In making decisions about the compensation of our executive officers, the Compensation Committee relies primarily on its members’ general experience and expertise, on the advice of consultants and other advisors and its consideration of a number of factors, including the following:

These factors provide the framework for compensation decision-making and final decisions regarding the compensation opportunity for each executive officer. No single factor is determinative in setting compensation levels.

The Compensation Committee does not engage in formal benchmarking against other companies’ compensation programs or practices to establish our compensation levels or make specific compensation determinations with respect to our executive officers. Instead, in making recommendations and determinations, the Compensation Committee reviews information summarizing the compensation paid at a representative group of peer companies, to the extent that the executive positions at these companies are considered comparable to our positions and informative of the competitive environment, and more broad-based compensation surveys to gain a general understanding of market compensation levels.

In addition, the Compensation Committee does not weight the foregoing factors in any predetermined manner, nor does it apply formulas in making its compensation determinations. The members of the Compensation Committee consider all of this information in light of their individual experience, knowledge of the Company and its business results, knowledge of the competitive market, knowledge of each executive officer, the advice of their compensation consultant and their business judgment in making their recommendations and determinations.

As part of its oversight function, our Board and our Compensation Committee in particular, along with our management team, considers potential risks when reviewing and approving various compensation programs, including executive compensation. Based on this review, our Compensation Committee believes that our compensation programs, including executive compensation, do not encourage risk taking to a degree that is reasonably likely to have a materially adverse impact on us or our operations.

Role of Management

In discharging its responsibilities, the Compensation Committee works with our CEO, who assists the Compensation Committee by providing information on corporate and individual performance, perspectives on performance issues and recommendations on compensation matters.

Typically, our CEO will make recommendations to the Compensation Committee regarding compensation matters, including adjustments to annual cash compensation, long-term incentive compensation opportunities, and program structures, for our executive officers, including our other Named Executive Officers. At the beginning of each year, our CEO reviews the performance of our executive officers based on each such individual’s level of success in accomplishing the business objectives established for him or her for the prior year and his or her overall performance during that year, and then shares these evaluations with, and makes recommendations to, the Compensation Committee for each element of compensation as described above. The Compensation Committee reviews and discusses these recommendations and proposals with our CEO.

engaged, the compensation consultant reports directly to the Compensation Committee and its chair, and serves at the discretion of the Compensation Committee, which reviews the engagement on a periodic basis.

For 2018, theOur Compensation Committee retainedhas selected Compensia, Inc. (“Compensia”), a national compensation consulting firm, to serve as its compensation advisor to advise on executive compensation matters, including competitive market pay practices for our executive officers, including our Named Executive Officers, and to offer an analysis of the compensation practices of a peer group that is assessed on a periodic basis.

During 2018, Compensia attended meetings of thematters. The Compensation Committee (both withgenerally engages Compensia every other year to advise on executive non-equity and without management present) as requestedequity compensation and provided the following services:

“peer companies.” During 2021, Compensia did not provide any services to our company other than the consulting services provided to theor Compensation Committee.

The Compensation Committee reviews the objectivity and independence of the advice provided by its compensation consultantCompensia on executive compensation matters. Thematters in the years in which it engages Compensia. For years in which the Compensation Committee has evaluatedengages Compensia, the Compensation Committee evaluates Compensia’s engagement and based on the six factors for assessing independence and identifying potential conflicts of interest that are set forth in Exchange Act Rule10C-1(b)(4), Rule 5605(d)(3)(D) of the NASDAQ Marketplace Rules, and such other factors as wereare deemed relevant under the circumstances, has determined that its relationship with Compensia and the work of Compensia on behalf of thecircumstances. The Compensation Committee did not raise any conflict of interest, and that Compensia is independent.undertake this review in 2021.

Competitive Positioning

For purposes of assessing our executive compensation against the competitive market, the Compensation Committee reviews and considers the compensation levels and practices of a select group of peer companies. This compensation peer group consists of technology companies that share one or more characteristics of our company, including annual revenue, market capitalization, geographical location, vertical focus and end market. However, not all criteria may be applicable to each individual peer group member.

Compensation Elements

In 2018,2021, the principal elements of our executive compensation program, and the purposes for each element, were as follows:

The base salaries of our Named Executive Officers for 20182021 were as follows:

Executive Bonus Program

Each year, we make bonus arrangements with our senior executives (including the Named Executive Officers), other employees who report directly to our CEO, and vice presidents in key positions (the “Executive Bonus Program”). Participants in the Executive Bonus Program are eligible to receive a bonus payment in the discretion of the Compensation Committee based upon the attainment of performance objectives as proposed by the CEO and approved by the Compensation Committee and which relate to the financial metrics that are most important to us.

Generally, for the Named Executives other than the CEO, bonus payments under the Executive Bonus Program are calculated starting with a target bonus amount for each participant as recommended by our CEO and approved by the Compensation Committee. Bonuses are then generally determined by measurement of Company performance against adjusted EBITDA that may be further adjusted in the discretion of the Compensation Committee multiplied byto exclude certain revenues and expenses that the achievement of a corporate financial performance metricCommittee believes should not impact compensation results (the “Company Performance Target”) with further consideration and then, for each program participant, adjusted for his or heradjustments given to individual performance. For the CEO, the Compensation Committee begins with a target bonus amount and then evaluates the CEO’s performance against certain quantitative and qualitative metrics associated with Company and individual performance. In each case,performance (the “CEO Metrics”). The Company generally does not disclose the Company Performance Target or the CEO Metrics since they are internal standards primarily used to assess compensation, and the Company believes that the disclosure of such information would cause competitive harm without adding meaningfully to the understanding of our business or compensation strategy. The Compensation Committee strives to set Company Performance Targets and CEO Metrics that are attainable but require significant management effort and achievement in order to be attained.

The Compensation Committee reviews the payment and amount of any award.

The 2021 cash bonuses were paid to the Named Executive Officers in February 2022 after the final bonus amountamounts for 2021 were determined.

In connection with the termination of Mr. Morof’s services, we entered into a transition and separation and general release agreement with him on January 15, 2021. The terms of that agreement provided for Mr. Morof to receive a cash bonus for the period from January 1, 2021 through March 16, 2021, based upon the average of the cash bonuses received by Mr. Morof for 2019 and 2020 pro-rated for the portion of calendar 2021 during which Mr. Morof was determined subsequent toyear-end. No provision was made for repayment of these installments if 2018 performance objectives were not attained; in fact, the performance objectives utilizedemployed by the Compensation Committee in 2018 were attained.us.

Target Bonus Amounts

For purposes of the Executive Bonus Program, bonus payments are based upon a specific target bonus amount as recommended by our CEO and approved by the Compensation Committee. The CEO participates in the Compensation Committee’s deliberations regarding the target amounts for eligible employees, but does not participate in the deliberations regarding his target bonus.

In February 2018,March 2021, the Compensation Committee reviewed the recommended target bonus amounts for our Named Executive Officers, taking into consideration the factors described in “Compensation-Setting Process – Setting Target Total Direct Compensation” above. Following this review, the Compensation Committee determined to set the target bonus amounts as proposed by our CEO with respect to the Named Executive Officers other than himself. The Compensation Committee independently reviewed and determined the CEO’s target bonus. For 2018,2021, the target bonus amounts for our Named Executive Officers were as follows:

Corporate Performance Metric and Individual Performance Metric

Participants in the Executive Bonus Program are eligible to receive a bonus payment in the discretion of the Compensation Committee based upon the attainment of performance objectives as proposed by the CEO and approved by the Compensation Committee and which relate to the financial metrics that are most important to us. For the Named Executive Officers (other than the CEO), the bonus was determined for 2018 by measurement of (i) Company performance against a variant of adjusted EBITDA that is further adjusted in the discretion of the Compensation Committee to exclude certain revenues and expenses that the Committee believes should not impact compensation results (the “Company Performance Target”); and (ii) individual performance. For the CEO, the bonus was determined for 2018 by measurement against a combination of quantitative and qualitative Company and individual performance metrics designed to promote growth of Company revenues and profitability (the “CEO Metrics”). The Company has chosen not to disclose the Company Performance Target or the CEO Metrics since they are internal standards primarily used to assess compensation, and the Company believes that disclosure of such information would cause competitive harm without adding meaningfully to the understanding of our business or compensation strategy. At the time they were set, the Company Performance Target and the CEO Metrics were perceived by the Compensation Committee to be attainable but requiring significant management effort and achievement in order to be attained.

Based on these determinations, the Compensation Committee approved the following cash bonus payments for our Named Executive Officers for 2018:2021:

Other than the amounts described above, we did not pay our Named Executive Officers any other annual cash bonuses in 2018.with respect to 2021 performance.

Long-Term Incentive Compensation

We view long-term incentive compensation in the form of equity awards as a critical element of our executive compensation program. The realized value of these equity awards bears a direct relationship to our stock price, and, therefore, these awards are an incentive for our executive officers, including our Named Executive Officers, to create value for our stockholders. Equity awards also help us retain qualified executive officers in a competitive market.

Long-term incentive compensation opportunities in the form of equity awards are granted to our CEO and our other executive officers by the Compensation Committee. The amount and forms of such equity awards are determined by the Compensation Committee after considering the factors described in “Compensation-Setting Process” above. The amounts of the equity awards are also intended to provide resulting target total direct compensation opportunities that the Compensation Committee believes are reasonable.

In January 2018,March 2021, the Compensation Committee determined that the equity awards to be granted to our executive officers, including our Named Executive Officers, should be in the forma combination of time-based RSU awards that may vest and be settled for shares of our Class A Common Stock and options to acquire our Class A Common Stock. The number of shares of our Class A Common Stock subject to the RSU awards and options granted to our executive officers (other than the CEO) were proposed by the CEO and approved by the Compensation Committee after considering the factors described in “Compensation-Setting Process” above. All of the RSU awards and options were granted in January 2018, except forMarch 2021 with respect to 2020 performance. Under applicable SEC regulations, such equity awards are included in the Summary Compensation Table below as 2021 compensation.

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RSU award forThe equity awards granted to our CEO, which the Compensation Committee determined and grantedNamed Executive Officers in March 2021 were as follows:

In February 2018. Subsequently,2022, the Compensation Committee determined that the equity awards to the extent that equity incentive awards arebe granted in the future, equity incentive awards forto our executive officers, including our Named Executive Officers willother than our CEO, should be a combination of time-based RSU awards that may vest and be settled for shares of our Class A Common Stock and options to acquire our Class A Common Stock. The number of shares of our Class A Common Stock subject to the RSU awards and options granted to our executive officers were proposed by the CEO and approved by the Compensation Committee (with Mr. Scapa participating in determinations regarding the grants other than the grants made to him in March 2022) after considering the factors described in “Compensation-Setting Process” above. The Compensation Committee also determined in March 2022 that the equity awards to be granted shortly after we publicly announceto ouryear-end earnings. CEO should be a combination of time-based RSU awards that may vest and be settled for shares of our Class A Common Stock and options to acquire our Class A Common Stock. All of the RSU awards and options were granted in February 2022 and March 2022 with respect to 2021 performance. Under applicable SEC regulations, such equity awards are not included in the Summary Compensation Table below as 2021 compensation.

The equity awards granted to our Named Executive Officers in 2018February and March 2022 were as follows:

The time-based RSU awards and stock options vest in equal annual installments over a four-year period, with each installment vesting on the anniversary of the date of grant, contingent upon each Named Executive Officer’s remaining continuously employed by us through each applicable vesting date. Upon vesting, the RSU awards may be settled by issuing that number of shares of our Class A Common Stock that equal the number of units that have vested.

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Health and Welfare Benefits

OurUS-based Named Executive Officers (excluding Mr. Fariello) are eligible to receive the following health and welfare benefits: a flexible spending account,a dependent care account,medical, dental, and vision insurance, business travel insurance, an employee assistance program, accidental death and dismemberment insurance, short-term and long-term disability insurance and basic life insurance.

We have also establishedSince 1987, Altair has offered atax-qualified 401(k) retirement savings plan for our US basedUS-based employees, including ourUS-based executive officers and ourUS-based Named Executive Officers, and other employees who satisfy certain eligibility requirements. In 2022, Altair added the Roth 401(k) feature to the plan. The Roth feature allows our employees to invest post-tax dollars and in retirement, access their money tax free. Under this plan, participants may elect to makepre-tax contributions of up to 80% of their eligible compensation, subject to the statutory income tax limits. The 401(k) Plan permits us to make discretionary matching contributions and discretionary contributions to eligible participants, subject to five-year graded vesting: 20% vests after one year, 40% after two years, 60% after three years, 80% after four years, and 100% after five years. The 401(k) Plan has an automatic enrollment feature for all employees hired on or after April 1, 2014, automatically withholding elective deferrals equal to 3%4% of eligible compensation, unless the participant affirmatively changes the deferral amount. We intend for the plan to qualify under Section 401(a) of the Internal Revenue Code (the “Code”) so that contributions by participants to the plan, and income earned on plan contributions, are not taxable to participants until withdrawn from the plan.

We design our employee benefits programs to be affordable and competitive in relation to the market as well as compliant with applicable laws and practices. We adjust our employee benefits programs as needed based upon regular monitoring of applicable laws and practices and the competitive market.

Perquisites and Other Personal Benefits

The Company owns a fractional interest in an airplane intended to be used primarily for business travel by our Chief Executive Officer and by other employees travelling with our Chief Executive Officer, and which may be used by other employees with the approval of our Chief Executive Officer. We believe that use of the Company airplane enhances personal safety and increases time available for business purposes. Our Chief Executive Officer and his guests may use our corporate airplane for non-business purposes. For 2021, the aggregate incremental cost to Altair of our Chief Executive Officer’s personal use of our corporate airplane was $284,418. No other Named Executive Officers made personal use of our corporate airplane during 2021.

We determine the incremental cost of the personal use of our corporate airplane based on the variable operating costs to us, which includes, if applicable, (i) landing, ramp, and parking fees and expenses; (ii) crew travel expenses; (iii) supplies and catering; (iv) aircraft fuel and oil expenses per hour of flight; (v) any customs, foreign permit, and similar fees; (vi) crew travel; and (vii) passenger ground transportation. Because our corporate airplane is intended to be used primarily for business travel, this methodology excludes fixed costs that do not change based on usage, such as purchase or lease costs and costs of maintenance and upkeep.

Our Named Executive Officers incur taxable income for all personal use of our corporate airplane. We do not grant bonuses to cover, reimburse, or otherwise “gross-up” any income tax owed for personal travel on our corporate aircraft.

Currently, we do not view perquisites or other personal benefits as a significant component of our executive compensation program. Accordingly, we do not provide any other significant perquisites or other personal benefits to our executive officers, including our Named Executive Officers, except as generally made available to our employees, or in situations where we believe it is appropriate to assist an individual in the performance of his or her duties, to make him or her more efficient and effective, and for recruitment and retention purposes.

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In the future, we may provide perquisites or other personal benefits in limited circumstances. All future practices with respect to perquisites or other personal benefits will be approved and subject to periodic review by the Compensation Committee.

Employment Agreements

We have entered into a written employment offer letterletters with our former CFO, Howard Morof, with our CFO, Matthew Brown and a consulting agreement with AShF, a Società a Responsabilità Limitata incorporated under the laws of Italy, which is wholly-owned by Mr. Fariello. This consulting agreement was entered into effective January 1, 2017 and was subsequently amended effective as of January 1, 2017.our CPO, Gilma Saravia. Neither our CEO nor any of our other Named Executive Officers is a party to an employment agreement or offer letter with us.

In the case of theDuring his employment as our CFO, Mr. Morof’s employment offer letter with Mr. Morof, this agreement providesprovided for “at will” employment (meaningmeaning that either we or Mr. Morof maywere able to terminate the employment relationship at any time without cause)cause, and setsset forth the then-current compensation arrangements for him,Mr. Morof, including his base salary, participation in a profit and growthour executive bonus pool,program, and participation in our standard employee benefit programs. In addition, thisMr. Morof’s employment offer letter providesprovided that Mr. Morof will bewas eligible to receive certain severance payments and benefits in connection with certain terminations of employment, as well asincluding a cash bonus payment if his employment iswas terminated in connection with a change in control of the Company. These post-employment compensation arrangementsAs of the close of business on March 16, 2021, Mr. Morof’s employment as our CFO terminated. In connection with the termination of Mr. Morof’s services, we entered into a transition and separation and general release agreement with him on January 15, 2021. The terms of that agreement with Mr. Morof are discussed in “Post-Employment Compensation” below.

InMr. Brown’s and Ms. Saravia’s employment offer letters also provide for “at will” employment, and set forth the current compensation arrangements for Mr. Brown and Ms. Saravia, including, in each case, of the consulting agreement with AShF, this agreement provides for a term of one year, which is renewed automatically for additional successiveone-year terms in the absence of either party providing notice of termination upon 60 days prior written notice. Under the terms of the consulting agreement, AShF must make Mr. Fariello available to provide services to us. In consideration for these services, we must pay AShF an annual consulting fee, providebase salary, participation in our executive bonus compensation program, through the payment of an incentive fee, and make a special payment equal to fifty percent of the sum of each consulting fee payment and each incentive fee payment. Sixty percent of such incentive fee (including the 50% special payment paid thereon) is to be paidparticipation in monthly installments and the balance of the incentive fee is to be paid at such time or times as comparable incentives are paid to other participants in the executive bonus program. The consulting agreement also prohibits AShF from disclosing our confidential information or business practices. Pursuant to the consulting agreement, AShF has entered into our standardnon-disclosure and intellectual property rights agreement. employee benefit programs.

For detailed descriptions of the employmentThe post-employment compensation arrangements we maintained withfor our Named Executive Officers during 2018, seeare discussed in “Narrative Disclosure to Summary Compensation TablePost Employment Compensation” and “Potential Payments Upon Termination orChange in Control” below.

Post-Employment Compensation

We do not providehave entered into executive severance payments and benefits toagreements with each of our Named Executive Officers, other than to Mr. Morof pursuant(the “Severance Agreements”). The Severance Agreements each provide for severance protections in the event of a termination by the Company other than for “cause” or in the event of a resignation by the applicable Named Executive Officer for “good reason” during the period between the execution of the Severance Agreements and the one-year anniversary of a “change in control.” In such event, the executive generally would be entitled to the following (in lieu of any other severance payments to which the executive may be entitled), subject to execution of a release of claims (other than with respect to certain amounts that accrued prior to termination):

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The Severance Agreements provide that to the extent any amount or benefit to be provided pursuant to the applicable Severance Agreement or otherwise would be treated as an “excess parachute payment,” as that phrase is involuntarily terminated for any reason other than “cause” (as defined in Section 280G of the amendedCode, then the amounts and restated employment offer letter)benefits the executive would otherwise receive would either be (i) paid or he voluntarily terminatesallowed in full; or (ii) reduced (but not below zero) to the maximum amount which may be paid without causing any amount or benefit to be nondeductible to the Company under Section 280G of the Code, or subject the executive to an excise tax under Section 4999 of the Code, whichever would result in the executive’s receipt, on an after-tax basis, of the greatest amount of amounts and benefits.

In connection with the termination of Mr. Morof’s services as of the close of business on March 16, 2021, we entered into a transition and separation and general release agreement with him on January 15, 2021. The separation agreement with Mr. Morof provided, among other things, for Mr. Morof to receive the following:

In addition, the separation agreement with Mr. Morof provided that letter).upon the effectiveness of his reaffirmation of his release of claims any outstanding unvested stock options and restricted stock units held by Mr. Morof will vest to the extent that such stock options and restricted stock units would have vested had Mr. Morof remained employed with us through March 16, 2022. Accordingly, 8,847 stock options and 2,337 restricted stock units held by Mr. Morof vested upon the effectiveness of his reaffirmation. Based upon the closing price of our Class A common stock of $60.02 on March 24, 2021 (the effective date of Mr. Morof’s reaffirmation of his release of claims), such stock options had a value of $387,317 and such restricted stock units had a value of $140,237.

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We do not use excise tax payments (or“gross-ups”) relating to a change in control of the Company and have no such obligations in place with respect to any of our Named Executive Officers.

For a summary of the material terms and conditions ofmore information about the post-employment compensation arrangements we maintained with our Named Executive Officers during 2018,2021, as well as an estimate of the potential payments and

Compensation Committee Report

The information contained in the following report of Altair’s compensation committee is not considered to be “soliciting material,” “filed” or incorporated by reference in any past or future filing by us under the

2021 Summary Compensation Table

Our Named Executive Officers for the year ended December 31, 20182021 are: James R. Scapa, Howard N. Morof, Matthew Brown, Gilma Saravia, Brett Chouinard and Uwe Schramm, and Massimo Fariello.Schramm. Mr. Morof served as our Chief Financial Officer through March 16, 2021. At the close of business on March 16, 2021, Matthew Brown became our Chief Financial Officer. The following table provides information regarding the total compensation for services rendered in all capacities earned by our Named Executive Officers for the fiscal years ended December 31, 2018, 20172021, 2020 and 2016.2019.

Narrative Disclosure to Summary Compensation Table

Employment Agreements with our Named Executive Officers

James Scapa, Brett Chouinard and Uwe Schramm

Mr. Scapa, Mr. Chouinard and Dr. Schramm are not a party to an employment agreement or offer letter with Altair.

Offer Letter with Gilma Saravia

We are parties to an employment letter with Gilma Saravia, our chief people officer. The employment letter has an indefinite term, and Analysis”.Ms. Saravia’s employment is at-will.

If Mr. Morof resigns from employment for good reason, or is terminated without cause, heMs. Saravia is entitled to 12 months of base salary plus any accruedan automobile allowance and she is currently eligible to earn annual bonus and a prorated annual bonus for the year of termination. He is also entitled to continued participation in our employee benefit programs, as if still employed as chief financial officer, during that 12 month period.

Pursuant to Mr. Morof’s employment letter, if Mr. Morof is involuntarily terminated for any reason other than cause or if Mr. Morof voluntarily terminates his employment for good reason within the one month prior to, or twelve months following, a change in control (as defined in our 2012 Plan (as defined under the heading “Equity Compensation Plans” below)) Mr. Morof will also be entitled to aone-time special bonus equal to $500,000,incentive compensation payable in full within three business days following such termination.

For purposes of Mr. Morof’s employment letter, “cause” means the occurrence of any of the following:

For purposes of Mr. Morof’s employment letter, “good reason” means the occurrence of any of the following:

Mr. Morof is required to provide written notice of any such good reason condition and we will have 30 days from receipt of such written notice to remedy such condition.

AShF, Srl Consulting Agreement

We entered into a consulting agreement with AShF, a Società a Responsabilità Limitata incorporated under the laws of Italy, which is effective as of January 1, 2017 and was subsequently amended effective as of January 1, 2017. AShF is wholly-owned by our Senior Vice President, Chief of Research and Development, Massimo Fariello, and Mr. Fariello serves as chief executive officer of AShF.

Potential Payments Upon Termination or Change in Control

The table below reflects, as applicable, cash severance, equity acceleration, and continuation of employment benefits payable to our Named Executive Officers in connection with (1)(A) an involuntary termination of employment (i.e., a termination without cause or resignation for good reason) other than in connection with a change in control of our Company, (2)company, (B) a change in control of our Companycompany and no termination of employment (assuming that all equity awards will not be assumed, continued or substituted by the successor entity), and (3)(C) an involuntary termination (i.e., a termination without cause or resignation for good reason) within one month prior to a change in control or twelve monthsimmediately following a change in control of our company, assuming for each of (1)(A), (2)(B) and (3)(C) that the applicable triggering event(s) occurred on December 31, 2018.2021, and that the above-mentioned severance agreements were in effect on that date. Generally, however, on any termination, the applicable Named Executive Officer would have received accrued and unpaid salary and other benefits until the date of termination. In addition, the table below assumes that our Named Executive Officers comply with all applicable restrictive covenants.

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Grants of Plan-Based Awards in Fiscal Year 20182021

The following table provides information regarding plan-based awards granted to our Named Executive Officers during 2018.2021.