Form: DEFA14A

Additional definitive proxy soliciting materials and Rule 14(a)(12) material

April 30, 2026

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549


SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No.   )


Filed by the Registrant

Filed by a Party other than the Registrant

Check the appropriate box:

Preliminary Proxy Statement

Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

Definitive Proxy Statement

Definitive Additional Materials

Soliciting Material under §240.14a-12

CLEAN ENERGY FUELS CORP.

(Name of Registrant as Specified in its Charter)

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

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

No fee required.

Fee paid previously with preliminary materials.

Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

GRAPHIC

Your Vote Counts! *Please check the meeting materials for any special requirements for meeting attendance. Smartphone users Point your camera here and vote without entering a control number For complete information and to vote, visit www.ProxyVote.com Control # V96651-P40523 CLEAN ENERGY FUELS CORP. 2026 Annual Meeting Vote by June 9, 2026 11:59 PM ET You invested in CLEAN ENERGY FUELS CORP. and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy materials for the stockholder meeting to be held on June 10, 2026. Vote Virtually at the Meeting* June 10, 2026 9:00 AM PDT Virtually at: www.virtualshareholdermeeting.com/CLNE2026 Get informed before you vote View the Annual Report and Notice and Proxy Statement online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 27, 2026. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. CLEAN ENERGY FUELS CORP. 4675 MACARTHUR COURT, SUITE 800 NEWPORT BEACH, CA 92660

GRAPHIC

Vote at www.ProxyVote.com Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Delivery Settings”. Voting Items Board Recommends V96652-P40523 THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. 1. To elect six directors to the Board of Directors For All Nominees: 01) Barclay F. Corbus 02) Stephen A. Scully 03) Lizabeth A. Ardisana 04) Patrick J. Ford 05) Andrew J. Littlefair 06) Vincent C. Taormina 2. To ratify the appointment of KPMG LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2026. For 3. To approve, on an advisory, non-binding basis, the compensation of our named executive officers. For NOTE: Such other business as may properly come before the meeting or any adjournment or postponement thereof.