Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MSD CAPITAL L P
   2. Issuer Name and Ticker or Trading Symbol
SemGroup Energy Partners, L.P. [SGLP] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
645 FIFTH AVENUE, 21ST FLOOR		 3. Date of Earliest Transaction (Month/Day/Year)
08/25/2008
(Street)

NEW YORK, NY 10022		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock (1) (2) 08/25/2008   P   123,200 A $ 9.9799 (3) 2,271,700 I See Footnote (1)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MSD CAPITAL L P
645 FIFTH AVENUE
21ST FLOOR
NEW YORK, NY 10022		     X    
MSD Torchlight, L.P.
645 FIFTH AVENUE
21ST FLOOR
NEW YORK, NY 10022		     X    

Signatures

 MSD Capital, L.P. By: MSD Capital Management LLC Its: General Partner By: /s/ Marc R. Lisker Name: Marc R. Lisker Title: Manager and General Counsel   08/27/2008
**Signature of Reporting Person Date
 MSD Torchlight, L.P. By: MSD Capital, L.P. Its: General Partner By: MSD Capital Management LLC Its: General Partner By: /s/ Marc R. Lisker Title: Manager and General Counsel   08/27/2008
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) This statement is jointly filed by and on behalf of each of MSD Capital, L.P. ("MSD Capital") and MSD Torchlight, L.P. ("MSD Torchlight"). Following the transactions reported herein, MSD Torchlight is the record and direct beneficial owner of 2,271,700 shares of common stock of SemGroup Energy Partners, L.P. MSD Capital is the general partner of MSD Torchlight and may be deemed to indirectly beneficially own securities owned by MSD Torchlight. MSD Capital Management LLC is the general partner of MSD Capital.
(2) Each reporting person states that neither the filing of this statement nor anything herein shall be deemed an admission that such person is, for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise, the beneficial owner of any securities covered by this statement. Each reporting person disclaims beneficial ownership of the securities covered by this statement, except to the extent of the pecuniary interest of such person in such securities.
(3) This transaction was executed in multiple trades on August 25, 2008 at prices ranging from $9.96 to $9.98. The price reported above reflects the weighted average purchase price. The reporting person(s) hereby undertake to provide to the Commission staff, the issuer or a security holder of the issuer, upon request, full information regarding the number of shares purchased at each separate price.
 
Remarks:
Exhibit 99.1 - Joint Filer Information (furnished herewith)

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