UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM SD

Specialized Disclosure Report

CLEAN ENERGY FUELS CORP.

(Exact Name of Registrant as Specified in Charter)

J. Nathan Jensen

Vice President and General Counsel

Clean Energy Fuels Corp.

4675 MacArthur Court, Suite 800

Newport Beach, California 92660

(949) 437-1000

(Name and Telephone Number, including area code,
of the person to contact in connection with this report.)

Check the appropriate box to indicate the rule pursuant to which this form is being filed, and provide the period to which the information in this form applies:

x          Rule 13p-1 under the Securities Exchange Act (17 CFR 240.13p-1) for the reporting period from January 1 to December 31, 2015.

Section 1 — Conflict Minerals Disclosure

Item 1.01                   Conflict Minerals Disclosure and Report.

Conflict Minerals Disclosure

This Form SD of Clean Energy Fuels Corp. (the “Company”) is filed pursuant to Rule 13p-1 promulgated under the Securities Exchange Act of 1934 for the reporting period January 1, 2015 to December 31, 2015.

A copy of the Company’s Conflict Minerals Report is provided as Exhibit 1.01 to this Form SD, is hereby incorporated by reference herein, and is publicly available at http://investors.cleanenergyfuels.com/corporate-governance.cfm The foregoing website reference is intended to be an inactive textual reference and the contents of the Company’s website are not incorporated into this report.

Item 1.02                   Exhibit.

The Conflict Minerals Report required by Item 1.01 of Form SD is filed as Exhibit 1.01 to this Form SD.

Section 2 — Exhibits

Item 2.01                   Exhibits

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the duly authorized undersigned.

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EXHIBIT INDEX

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