<PAGE>
THIS FILING LISTS SECURITIES HOLDINGS REPORTED
ON THE FORM 13F FILED ON AUGUST 16, 1999
PURSUANT TO A REQUEST FOR
CONFIDENTIAL TREATMENT AND FOR WHICH
THAT REQUEST
EXPIRED ON AUGUST 14, 2000
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form 13F
FORM 13F COVER PAGE
Report for the Calendar Year or Quarter Ended: June 30, 1999
Check here if Amendment [x ]; Amendment Number: 4
This Amendment (Check only one.): [ ] is a restatement.
[x] adds new holdings entries.
Institutional Investment Manager Filing this Report:
Name: Chesapeake Partners Management Co., Inc.
Address: 1829 Reisterstown Road
Suite 220
Baltimore, Maryland 21208
Form 13F File Number: 28-4120
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: Mark D. Lerner
Title: Vice President
Phone: (410) 602-0195
Signature, Place, and Date of Signing:
/s/ Mark D. Lerner Baltimore, Maryland 8/14/2000
------------------ ------------------- ---------
[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).)
<PAGE>
FORM 13F SUMMARY PAGE
Report Summary:
Number of Other Included Managers: 0
------------------------
Form 13F Information Table Entry Total: 13
------------------------
Form 13F Information Table Value Total: $216,985
------------------------
(thousands)
List of Other Included Managers:
Provide a numbered list of 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.
[If there are no entries in this list, state "NONE" and omit the column headings
and list entries.]
None
<PAGE>
FORM 13F INFORMATION TABLE
<TABLE>
<CAPTION>
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7
--------------------- -------- ---------- -------- ----------------------- ---------- --------
TITLE OF VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER
NAME OF ISSUER CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGERS
<S> <C> <C> <C> <C> <C> <C> <C> <C>
Acceptance Insurance Common 004308102 1,342 89,100 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Aviall, Inc. Common 05366B102 9,880 525,200 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Aztec Technology Common 05480L101 1,916 996,946 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Celadon Group Common 150838100 1,788 210,300 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
CMP Group, Inc. Common 125887109 767 29,300 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Comsat Corp. Common 20564D107 9,792 301,300 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Foamex International Common 344123104 3,004 540,100 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Gucci Group NV Common 401566104 45,066 643,800 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
IPC Communications Common 44980K206 35,988 527,300 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
MediaOne Common 58440J104 70,522 948,200 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Qwest
Communications Common 749121109 4,133 125,000 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
Telecom Italia Common 87927W106 13,106 124,600 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
US West, Inc. Common 91273H101 19,681 335,000 SH SOLE
-------------------------------------------------------------------------------------------------------------------------
<CAPTION>
COLUMN 1 COLUMN 8
--------------------- -------------------------------
VOTING AUTHORITY
NAME OF ISSUER SOLE SHARED NONE
<S> <C> <C> <C>
Acceptance Insurance SOLE
--------------------------------------------------------------
Aviall, Inc. SOLE
--------------------------------------------------------------
Aztec Technology SOLE
--------------------------------------------------------------
Celadon Group SOLE
--------------------------------------------------------------
CMP Group, Inc. SOLE
--------------------------------------------------------------
Comsat Corp. SOLE
--------------------------------------------------------------
Foamex International SOLE
--------------------------------------------------------------
Gucci Group NV SOLE
--------------------------------------------------------------
IPC Communications SOLE
--------------------------------------------------------------
MediaOne SOLE
--------------------------------------------------------------
Qwest
Communications SOLE
--------------------------------------------------------------
Telecom Italia SOLE
--------------------------------------------------------------
US West, Inc. SOLE
--------------------------------------------------------------
</TABLE>
