Schedule 13G

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934
(Amendment No. ____)*

ATLAS PIPELINE PARTNERS, L.P.
(Name of Issuer)
Common Units
(Title of Class of Securities)
049392103
(CUSIP Number)
January 20, 2011
(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

     o Rule 13d-1(b)

     þ Rule 13d-1(c)

     o Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications:

Janice V. Sharry, Esq.
Haynes and Boone, LLP
2323 Victory Avenue, Suite 700
Dallas, Texas 75219-7673
(214) 651-5000

 
 

 

                     
CUSIP No.
  
049392103 
  

 

           
1   NAMES OF REPORTING PERSONS
MSD Capital, L.P.
     
     
2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
  (a)   o
  (b)   þ
     
3   SEC USE ONLY
   
   
     
4   CITIZENSHIP OR PLACE OF ORGANIZATION
   
  Delaware
       
  5   SOLE VOTING POWER
     
NUMBER OF   0
       
SHARES 6   SHARED VOTING POWER
BENEFICIALLY    
OWNED BY   3,500,000
       
EACH 7   SOLE DISPOSITIVE POWER
REPORTING    
PERSON   0
       
WITH: 8   SHARED DISPOSITIVE POWER
     
    3,500,000
     
9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
   
  3,500,000
     
10   CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
   
  o
     
11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
   
  6.6%
     
12   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
   
  PN

 

                     
CUSIP No.
  
049392103 
  

 

           
1   NAMES OF REPORTING PERSONS
SOF Investments, L.P.
     
     
2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
  (a)   o
  (b)   þ
     
3   SEC USE ONLY
   
   
     
4   CITIZENSHIP OR PLACE OF ORGANIZATION
   
  Delaware
       
  5   SOLE VOTING POWER
     
NUMBER OF   0
       
SHARES 6   SHARED VOTING POWER
BENEFICIALLY    
OWNED BY   1,000,000
       
EACH 7   SOLE DISPOSITIVE POWER
REPORTING    
PERSON   0
       
WITH: 8   SHARED DISPOSITIVE POWER
     
    1,000,000
     
9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
   
  1,000,000
     
10   CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
   
  o
     
11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
   
  1.9%
     
12   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
   
  PN

 

                     
CUSIP No.
  
049392103 
  

 

           
1   NAMES OF REPORTING PERSONS
MSD Energy Investments, L.P.
     
     
2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
  (a)   o
  (b)   þ
     
3   SEC USE ONLY
   
   
     
4   CITIZENSHIP OR PLACE OF ORGANIZATION
   
  Delaware
       
  5   SOLE VOTING POWER
     
NUMBER OF   0
       
SHARES 6   SHARED VOTING POWER
BENEFICIALLY    
OWNED BY   2,500,000
       
EACH 7   SOLE DISPOSITIVE POWER
REPORTING    
PERSON   0
       
WITH: 8   SHARED DISPOSITIVE POWER
     
    2,500,000
     
9   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
   
  2,500,000
     
10   CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
   
  o
     
11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
   
  4.7%
     
12   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
   
  PN

 

Item 1.
  (a)  
Name of Issuer
ATLAS PIPELINE PARTNERS, L.P.
  (b)  
Address of Issuer’s Principal Executive Offices
1550 Coraopolis Heights Road, Moon Township, Pennsylvania 15108
Item 2.
  (a)  
Name of Person Filing
This statement is jointly filed by and on behalf of each of MSD Capital, L.P., SOF Investments, L.P. and MSD Energy Investments, L.P. MSD Capital is the general partner of, and may be deemed to beneficially own securities owned by, each of SOF Investments and MSD Energy Investments. MSD Capital Management LLC is the general partner of, and may be deemed to beneficially own securities owned by, MSD Capital. Michael S. Dell is the controlling member of, and may be deemed to beneficially own securities owned by, MSD Capital Management. 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, the beneficial owner of any securities covered by this statement.
  (b)  
Address of Principal Business Office or, if none, Residence
The address of the principal business office of each reporting person is 645 Fifth Avenue, 21st Floor, New York, New York 10022.
  (c)  
Citizenship
 
     
See Item 4 on the cover page(s) hereto.
 
  (d)  
Title of Class of Securities
 
     
Common Units
 
  (e)  
CUSIP Number
 
     
049392103

 

 

 

Item 3.  
If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
  (a) o 
Broker or dealer registered under Section 15 of the Act (15 U.S.C. 78o).
 
  (b) o 
Bank as defined in Section 3(a)(6) of the Act (15 U.S.C. 78c).
 
  (c) o 
Insurance company as defined in Section 3(a)(19) of the Act (15 U.S.C. 78c).
 
  (d) o 
Investment company registered under Section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).
 
  (e) o 
An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);
 
  (f) o 
An employee benefit plan or endowment fund in accordance with §240.13d- 1(b)(1)(ii)(F);
 
  (g) o 
A parent holding company or control person in accordance with §240.13d- 1(b)(1)(ii)(G);
 
  (h) o 
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
 
  (i) o 
A church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
 
  (j) o 
A non-U.S. institution in accordance with §240.13d—1(b)(1)(ii)(J);
 
  (k) o 
A group, in accordance with §240.13d-1(b)(1)(ii)(K).
Item 4.  
Ownership.
  (a)  
Amount beneficially owned: See Item 9 on the cover page(s) hereto.
 
  (b)  
Percent of class: See Item 11 on the cover page(s) hereto.
 
  (c)  
Number of shares as to which such person has:
  (i)  
Sole power to vote or to direct the vote: See Item 5 on the cover page(s) hereto.
 
  (ii)  
Shared power to vote or to direct the vote: See Item 6 on the cover page(s) hereto.
 
  (iii)  
Sole power to dispose or to direct the disposition of: See Item 7 on the cover page(s) hereto.
 
  (iv)  
Shared power to dispose or to direct the disposition of: See Item 8 on the cover page(s) hereto.
Item 5.  
Ownership of 5% or Less of a Class.
If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following o.

 

 

 

Item 6.  
Ownership of More than 5 Percent on Behalf of Another Person.
Not Applicable
Item 7.  
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.  
Identification and Classification of Members of the Group.
Not Applicable
Item 9.  
Notice of Dissolution of Group.
Not Applicable
Item 10.  
Certifications
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

 

 

 

SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
         
Date: January 31, 2011   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   
 
  SOF INVESTMENTS, L.P.
 		  
  By:   MSD Capital, L.P.    
  Its:  General Partner   
     
  By:   MSD Capital Management LLC    
  Its:  General Partner   
     
  By:   /s/ Marc R. Lisker    
  Name:   Marc R. Lisker   
  Title:   Manager and General Counsel   
 
  MSD ENERGY INVESTMENTS, L.P.
 		  
  By:   MSD Capital, L.P.    
  Its:  General Partner   
     
  By:   MSD Capital Management LLC    
  Its:  General Partner   
     
  By:   /s/ Marc R. Lisker    
  Name:   Marc R. Lisker   
  Title:   Manager and General Counsel   
 

 

 

 

EXHIBIT INDEX
     
Exhibit   Description of Exhibit
 
    
99.1
  Joint Filing Agreement (furnished herewith)