UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 13F FORM 13F COVER PAGE Report for the Calendar Year or Quarter Ended: March 31, 2013 Check here if Amendment [ ]; Amendment Number: ______ This Amendment (Check only one.): [ ] is a restatement. [ ] adds new holdings entries. Institutional Investment Manager Filing this Report: Name: GCP Capital Partners LLC Address: 300 Park Avenue, 18th Floor New York, NY 10022 Form 13F File Number: 028-15391 --------- The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form. Person Signing this Report on Behalf of Reporting Manager: Name: V. Frank Pottow Title: Vice President Phone: 212-389-1515 Signature, Place, and Date of Signing: /s/ V. Frank Pottow New York, NY May 13, 2013 ---------------------------- ------------------------------- --------------- [Signature] [City, State] [Date] Report Type (Check only one.): [X] 13F HOLDINGS REPORT. (Check here if all holdings of this reporting manager are reported in this report.) [ ] 13F NOTICE. (Check here if no holdings reported are in this report, and all holdings are reported by other reporting manager(s).) [ ] 13F COMBINATION REPORT. (Check here if a portion of the holdings for this reporting manager are reported in this report and a portion are reported by other reporting manager(s).) List of Other Managers Reporting for this Manager: 0 FORM 13F SUMMARY PAGE Report Summary: Number of Other Included Managers: 1 ----------- Form 13F Information Table Entry Total: 1 ----------- Form 13F Information Table Value Total: $ 376,158 ----------- (thousands) List of Other Included Managers: Provide a numbered list of the name(s) and Form 13F file number(s) of all institutional investment managers with respect to which this report is filed, other than the manager filing this report. No. Form 13F File Number Name 1 - 028-15374 Metalmark Management II LLC ------- ---------------------- --------------------------- - ------- ---------------------- --------------------------- - ------- ---------------------- --------------------------- - ------- ---------------------- --------------------------- VOTING AUTHORITY FORM 13F INFORMATION TABLE VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER NAME OF ISSUER TITLE OF CLASS CUSIP (X$1000) PRN AMT PRN CALL DISCRETION MANAGERS SOLE SHARED NONE -------------- -------------- ---------- ----------- ----------- ------ ----- ------------ ---------- ---- --------- ----- PACIFIC COAST UNIT BEN INT 694103102 376,158 20,083,158 SH Shared-Other 1 Shared OIL TR