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)
07/21/2009
(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 Units (1) (2) (3) 07/21/2009   P   27,000 A $ 5.8556 3,559,394 I See footnote (4) (5)
Common Units (1) (2) (3) 07/23/2009   P   11,800 A $ 5.97 3,571,194 I See footnote (4) (6)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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, Title: Manager and General Counsel   07/23/2009
**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   07/23/2009
**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. and MSD Torchlight, L.P. MSD Capital is the general partner of MSD Torchlight and may be deemed to beneficially own securities owned by MSD Torchlight. MSD Capital Management LLC is the general partner of MSD Capital and may be deemed to beneficially own securities owned by MSD Capital. Michael S. Dell is the controlling member of MSD Capital Management and may be deemed to beneficially own securities owned by MSD Capital Management.
(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 Act 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) Each reporting person may be deemed to be a member of a group with respect to the issuer or securities of the issuer for the purposes of Section 13(d) or 13(g) of the Act. Each reporting person declares that neither the filing of this statement nor anything herein shall be construed as an admission that such person is, for the purposes of Section 13(d) or 13(g) of the Act or any other purpose, a member of a group with respect to the issuer or securities of the issuer.
(4) Represents securities owned by MSD Torchlight.
(5) This transaction was executed in multiple trades on July 21, 2009 at prices ranging from $5.81 to $5.90. The price reported reflects the weighted average purchase price. The reporting person(s) hereby undertake(s) to provide to the Commission staff, the issuer or a security holder of the issuer, upon request, full information regarding the number of securities purchased at each separate price.
(6) This transaction was executed in multiple trades on July 23, 2009 at prices ranging from $5.95 to $6.00. The price reported reflects the weighted average purchase price. The reporting person(s) hereby undertake(s) to provide to the Commission staff, the issuer or a security holder of the issuer, upon request, full information regarding the number of securities purchased at each separate price.

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