SC 13D/A 1 pge13d3c.txt PRIME GROUP 13D/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 Amendment #3 Prime Group Realty Trust ___________________________________________ (Name of Issuer) Common Stock ___________________________________________ (Title of Class and Securities) 74158J103 ___________________________________________ (CUSIP Number of Class of Securities) O. Mason Hawkins Chairman of the Board and C.E.O. and Charles D. Reaves Vice President & General Counsel Southeastern Asset Management, Inc. 6410 Poplar Avenue; Suite 900 Memphis, TN 38119 (901) 761-2474 ___________________________________________________________ (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) August 24, 2001 ___________________________________________ (Date of Event which Requires Filing of this Statement) If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this Schedule because of Sections 240.13d-1(e), 240.13d-1(f), or 240.13d-1(g), check the following box: [X] CUSIP No. 74158J103 13D ___________________________________________________________________ (1) NAMES OF REPORTING PERSONS Southeastern Asset Management, Inc. I.D. No. 62-0951781 ___________________________________________________________________ (2) CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP: (a) (b) X ___________________________________________________________________ (3) SEC USE ONLY ___________________________________________________________________ (4) SOURCE OF FUNDS OO: Funds of investment advisory clients ___________________________________________________________________ (5) CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ___________________________________________________________________ (6) CITIZENSHIP OR PLACE OF ORGANIZATION Tennessee ___________________________________________________________________ :(7) SOLE VOTING POWER : (Discretionary Accounts) NUMBER OF SHARES BENEFICIALLY : None OWNED BY EACH REPORTING PERSON ________________________________ WITH :(8) SHARED VOTING POWER : 0 shares ________________________________ :(9) SOLE DISPOSITIVE POWER : (Discretionary Accounts) : None ________________________________ :(10) SHARED DISPOSITIVE POWER : 0 shares ___________________________________________________________________ (11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 shares ___________________________________________________________________ (12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN SHARES ___________________________________________________________________ (13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11 0.0% ___________________________________________________________________ (14) TYPE OF REPORTING PERSON IA ___________________________________________________________________ CUSIP No. 74158J103 13D ___________________________________________________________________ (1) NAMES OF REPORTING PERSONS Longleaf Partners Realty Fund I.D. No. 62-1616883 ___________________________________________________________________ (2) CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP: (a) (b) X ___________________________________________________________________ (3) SEC USE ONLY ___________________________________________________________________ (4) SOURCE OF FUNDS OO: Assets of Longleaf Partners Realty Fund ___________________________________________________________________ (5) CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ___________________________________________________________________ (6) CITIZENSHIP OR PLACE OF ORGANIZATION Massachusetts ___________________________________________________________________ :(7) SOLE VOTING POWER : (Discretionary Accounts) NUMBER OF SHARES BENEFICIALLY : None OWNED BY EACH REPORTING PERSON ________________________________ WITH :(8) SHARED VOTING POWER : 0 shares ________________________________ :(9) SOLE DISPOSITIVE POWER : (Discretionary Accounts) : None ________________________________ :(10) SHARED DISPOSITIVE POWER : 0 shares ___________________________________________________________________ (11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 shares ___________________________________________________________________ (12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN SHARES ___________________________________________________________________ (13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11 0.0% ___________________________________________________________________ (14) TYPE OF REPORTING PERSON IV ___________________________________________________________________ CUSIP No. 74158J103 13D ___________________________________________________________________ (1) NAMES OF REPORTING PERSONS O. Mason Hawkins I.D. No. ###-##-#### ___________________________________________________________________ (2) CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP: (a) (b) X ___________________________________________________________________ (3) SEC USE ONLY ___________________________________________________________________ (4) SOURCE OF FUNDS OO: None ___________________________________________________________________ (5) CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e) [ ] ___________________________________________________________________ (6) CITIZENSHIP OR PLACE OF ORGANIZATION Citizen of United States ___________________________________________________________________ :(7) SOLE VOTING POWER : (Discretionary Accounts) NUMBER OF SHARES BENEFICIALLY : None OWNED BY EACH REPORTING PERSON ________________________________ WITH :(8) SHARED VOTING POWER : None ________________________________ :(9) SOLE DISPOSITIVE POWER : None ________________________________ :(10) SHARED DISPOSITIVE POWER : None ___________________________________________________________________ (11) AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON None (See Item 2) ___________________________________________________________________ (12) CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN SHARES ___________________________________________________________________ (13) PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11 0.0% ___________________________________________________________________ (14) TYPE OF REPORTING PERSON IN ___________________________________________________________________ Item 1. Security and Issuer The class of equity security to which this statement on Schedule 13D relates is the common stock (the "Securities") of Prime Group Realty Trust, a Maryland corporation (the "Issuer"). The Issuer has its principal executive offices located at 77 West Wacker Drive, Suite 3900, Chicago, Illinois 60601. Item 2. Identity and Background This statement is being filed by Southeastern Asset Management, Inc. ("Southeastern"), an investment advisor registered with the Securities & Exchange Commission under the Investment Advisers Act of 1940, as amended. The address of its principal office is 6410 Poplar Avenue, Suite 900, Memphis, Tennessee 38119. Southeastern serves as an investment advisor to various individual clients, institutions (including qualified retirement plans), endowment funds and to Longleaf Partners Funds Trust ("Longleaf"), a registered investment company organized as a Massachusetts business trust and having four series or portfolios. This amendment #3 to Schedule 13D has been filed to indicate that, as of August 24, 2001, Southeastern's clients, including Longleaf Partners Realty Fund, no longer owned any Securities of the issuer. Accordingly, Items 5(a) and 5(c) are hereby amended as follows: Item 5. Interest In Securities Of The Issuer (a) As of August 24, 2001, Southeastern's clients, including Longleaf Partners Realty Fund, no longer owned any Securities of the Issuer. Common % of outstanding Shares Common Shares Held _________________________________________________________________ __ Voting Authority Shared: 0 0.0% Total 0 0.0% Dispositive Authority Shared: 0 0.0% Total 0 0.0% (b) There have been the following sales of the Securities by discretionary accounts during the past sixty days, made in the open market through the NASDAQ National Market: Date # of Shares Aggregate Price Avg. Price 6/26/01 24,500 314,332 12.83 7/12/01 937,800 12,594,232 13.43 7/23/01 5,000 69,648 13.93 7/25/01 14,200 194,108 13.67 8/09/01 4,100 55,184 13.46 8/10/01 4,900 66,099 13.49 8/14/01 3,400 44,878 13.20 8/15/01 5,900 77,995 13.22 8/22/01 3,600 45,826 12.73 8/24/01 1,658,700 23,074,300 13.91 SIGNATURES 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. Dated: August 29, 2001 SOUTHEASTERN ASSET MANAGEMENT, INC. By /s/ Charles D. Reaves _______________________________ Charles D. Reaves Vice President & General Counsel O. MASON HAWKINS (Individually) /s/ O. Mason Hawkins _______________________________ Longleaf Partners Realty Fund By: Southeastern Asset Management, Inc. By /s/ Charles D. Reaves _______________________________ Charles D. Reaves Vice President & General Counsel Joint Filing Agreement In accordance with Rule 13d-1(f) under the Securities Exchange Act of 1934, the persons or entities named below agree to the joint filing on behalf of each of them of this Schedule 13D with respect to the common stock of Prime Group Realty Trust, and further agree that this joint filing agreement be included in this filing. In evidence thereof, the undersigned hereby execute this Agreement on August 29, 2001. SOUTHEASTERN ASSET MANAGEMENT, INC. By /s/ Charles D. Reaves _______________________________ Charles D. Reaves Vice President & General Counsel O. MASON HAWKINS (Individually) /s/ O. Mason Hawkins _______________________________ Longleaf Partners Realty Fund By: Southeastern Asset Management, Inc. By /s/ Charles D. Reaves _______________________________ Charles D. Reaves Vice President & General Counsel Prime Group Realty Trust ("Issuer") Schedule 13D (Amendment #3) PGE13D3.doc