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Preliminary Proxy Statement

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Definitive Proxy Statement

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Soliciting Material Pursuant to §240.14a‑12

AXT, Inc.

(Name of Registrant as Specified In Its Charter)

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TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: E08099-P78334 KEEP THIS PORTION FOR YOUR RECORDS DETACH AND RETURN THIS PORTION ONLY THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. To withhold authority to vote for any individual nominee(s), mark “For All Except” and write the number(s) of the nominee(s) on the line below. AXT, INC. The Board of Directors recommends you vote FOR the following: For Withhold For All AllAllExcept ! ! ! 1. To elect One (1) Class III Director to hold office for a three-year term and until his successor is elected and qualified. Class III Director: 01) Leonard J. LeBlanc For Against Abstain The Board of Directors recommends you vote FOR proposals 2 and 3. ! ! ! ! ! ! 2. To approve, on an advisory basis, the compensation of AXT's named executive officers. 3. To ratify the appointment of Burr Pilger Mayer, Inc. as AXT's independent registered public accounting firm for the fiscal year ending December 31, 2016. NOTE: Such other business as may properly come before the meeting or any adjournment thereof. For address change/comments mark here. (see reverse for instructions) ! ! Yes ! No Please indicate if you plan to attend this meeting. Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Notice and Proxy Statement and Annual Report on Form 10-K are available at www.proxyvote.com.

AXT, INC. Annual Meeting of Stockholders May 26, 2016 11:00 a.m. This proxy is solicited by the Board of Directors The undersigned hereby constitutes and appoints Morris S. Young and Gary L. Fischer and each of them, as his or her true and lawful agents and proxies with full power of substitution and hereby authorizes them to represent the undersigned and to vote all of the shares of common stock in AXT, Inc., which the undersigned is entitled to vote at the 2016 Annual Meeting of Stockholders to be held at 4281 Technology Drive, Fremont, California on May 26, 2016 at 11:00 a.m. Pacific Daylight Time, and at any adjournment thereof (1) as hereinafter specified upon the proposals listed and as more particularly described in AXT's proxy statement, receipt of which is hereby acknowledged and (2) in their discretion upon such other matters as may properly come before the meeting. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors' recommendations. (If you noted any Address Changes and/or Comments above, please mark corresponding box on the reverse side.) Continued and to be signed on reverse side Address change/comments: