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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)

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CLEAN ENERGY FUELS CORP.

Meeting Information

Meeting Type:          Annual Meeting

For holders as of:    April 10,2018

Date:    May 30, 2018    Time: 9:00 AM PDT

Location:  Live via the Internet at

                  www.virtualshareholdermeeting.com/CLNE2018.

The company will be hosting the meeting live via the Internet this year. To attend the meeting via the Internet please visit www.virtualshareholdermeeting.com/CLNE2018 and be sure to have the information that is printed in the box marked by the arrow ÚXXXX XXXX XXXX XXXX (located on the following page).

CLEAN ENERGY FUELS CORP.

4675 MACARTHUR COURT, SUITE

800 NEWPORT BEACH, CA 92660

You are receiving this communication because you hold shares in the company named above.

This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side).

We encourage you to access and review all of the important information contained in the proxy materials before voting.

See the reverse side of this notice to obtain proxy materials and voting instructions.

Proxy Materials Available to VIEW or RECEIVE:

NOTICE, PROXY STATEMENT AND ANNUAL REPORT

How to View Online:

Have the information that is printed in the box marked by the arrow ÚXXXX XXXX XXXX XXXX (located on the following page) and visit: www.proxyvote.com.

How to Request and Receive a PAPER or E-MAIL Copy:

If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request:

1) BY INTERNET:

www.proxyvote.com

2) BY TELEPHONE:

1-800-579-1639

3) BY E-MAIL*:

sendmaterial@proxyvote.com

*  If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow ÚXXXX XXXX XXXX XXXX (located on the following page) in the subject line.

Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before May 16, 2018 to facilitate timely delivery.

Vote By Internet:

Before The Meeting:

Go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow ÚXXXX XXXX XXXX XXXX (located on the following page) available and follow the instructions.

During The Meeting:

Go to www.virtualshareholdermeeting.com/CLNE2018.  Have the information that is printed in the box marked by the arrow ÚXXXX XXXX XXXX XXXX (located on the following page) available and follow the instructions.

Vote By Phone: You can vote by telephone by requesting a paper copy of the proxy materials, which will include a proxy card that will provide instructions on how to vote your shares by proxy via telephone.

Vote By Mail: You can vote by mail by requesting a paper copy of the proxy materials, which will include a proxy card.

Voting Items

The Board of Directors recommends you vote

FOR ALL of the director nominees in proposal 1.

1.

Election of Directors

Nominees:

01)

Andrew J. Littlefair

06)

T. Boone Pickens

02)

Warren I. Mitchell

07)

Stephen A. Scully

03)

John S. Herrington

08)

Kenneth M. Socha

04)

James C. Miller III

09)

Vincent C. Taormina

05)

James E. O’Connor

The Board of Directors recommends you vote FOR proposals 2 and 3.

2.

Ratification of the appointment of KPMG LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2018.

3.

Approval, on an advisory, non-binding basis, of our executive compensation.

NOTE: To transact any other business that may properly come before the meeting or any adjournment or postponement of the meeting.