<PAGE>
THIS FILING LISTS SECURITIES HOLDINGS REPORTED
ON THE FORM 13F FILED ON MAY 14, 1999
PURSUANT TO A REQUEST FOR
CONFIDENTIAL TREATMENT AND FOR WHICH
THAT REQUEST WAS DENIED OR CONFIDENTIAL TREATMENT
EXPIRED ON SEPTEMBER 30, 1999
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form 13F
FORM 13F COVER PAGE
Report for the Calendar Year or Quarter Ended: March 31, 1999
Check here if Amendment [x]; Amendment Number: 1
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 10/07/99
[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: 68
Form 13F Information Table Value Total: $885,790
(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 COLUMN 8
- --------------------- ---------- --------- -------- -------------------- ---------- -------- ------------------
TITLE VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGERS SOLE SHARED NONE
- --------------------- ---------- --------- -------- --------- --- ---- ---------- -------- ---- ------ ----
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
Aeroquip Vickers Common 007869100 20,231 353,000 SH SOLE SOLE
Airtouch Comm. Common 00949t100 56,342 583,100 SH SOLE SOLE
Aliant Comm. Common 016090102 205 5,000 SH SOLE SOLE
American Stores Common 030096101 44,788 1,357,200 SH SOLE SOLE
AMP, Inc. Common 031897101 79,845 1,492,433 SH SOLE SOLE
Architel Systems Common 039917109 1,727 90,000 SH SOLE SOLE
Ascend Comm. Common 043491109 80,742 964,800 SH SOLE SOLE
ASTRA AB Common 046298105 15,623 681,100 SH SOLE SOLE
Ballard Medical Common 058566100 1,711 70,200 SH SOLE SOLE
Bankers Trust Common 066365107 75,657 857,300 SH SOLE SOLE
Browning Ferris Common 115885105 22,173 575,000 SH SOLE SOLE
Brylane, Inc. Common 117661108 8,420 347,200 SH SOLE SOLE
Capstar Broadcasting Common 14067g105 3,842 167,500 SH SOLE SOLE
Coltec Industries Common 196879100 7,260 399,200 SH SOLE SOLE
D&N Financial Common 232864108 323 14,200 SH SOLE SOLE
Diamond
Fields International Common 252905104 159 341,800 SH SOLE SOLE
Eagle Hardware Common 26959b101 5,915 154,900 SH SOLE SOLE
Eclipse Surgical Common 278849104 168 15,560 SH SOLE SOLE
Excite, Inc. Common 300904109 88,340 631,000 SH SOLE SOLE
Executive Risk Common 301586103 9,883 139,200 SH SOLE SOLE
FDP Corp. Common 302905104 1,043 65,200 SH SOLE SOLE
Filenes Basement Common 316866102 603 316,500 SH SOLE SOLE
Fleet Fin. Warrants Common 338915119 2,415 68,992 SH SOLE SOLE
Fleet Financial Common 338915101 1,776 47,200 SH SOLE SOLE
Fred Meyer, Inc. Common 592097109 19,458 330,500 SH SOLE SOLE
Frontier Corp Common 35906p105 519 10,000 SH SOLE SOLE
Geocities Common 37247v106 11,592 105,800 SH SOLE SOLE
Getchell Gold Common 374265106 4,276 163,300 SH SOLE SOLE
Gucci Group NV Common 401566104 16,865 209,500 SH SOLE SOLE
IPC Information Common 44980k206 17,968 933,400 SH SOLE SOLE
Irvine Apartments Common 463606103 5,299 161,200 SH SOLE SOLE
J Ray McDermott Common p64658100 299 10,000 SH SOLE SOLE
Kaynar Technologies Common 486605108 6,782 242,200 SH SOLE SOLE
Level One Comm. Common 527295109 32,681 672,100 SH SOLE SOLE
Lifeline Systems Common 532192101 2,467 103,600 SH SOLE SOLE
Lucasvarity PLC Common 549395101 14,733 317,300 SH SOLE SOLE
Lycos, Inc. Common 550818108 714 8,300 SH SOLE SOLE
Modis Professional Common 004401105 2,545 280,800 SH SOLE SOLE
Morton International Common 619331101 18,651 507,500 SH SOLE SOLE
Moviefone, Inc. Common 624598108 8,183 174,100 SH SOLE SOLE
Nac Re Corp. Common 628907107 2,684 50,000 SH SOLE SOLE
Neff Corp. Common 640094108 452 56,500 SH SOLE SOLE
Nextar Pharmaceutical Common 65333b106 4,966 291,000 SH SOLE SOLE
North Face, Inc. Common 659317101 3,356 268,500 SH SOLE SOLE
O'Sullivan Industries Common 688609106 138 10,000 SH SOLE SOLE
Oshap Tech Ltd. Common 671039105 5,705 436,700 SH SOLE SOLE
Pioneer HiBred Common 723686101 9,553 253,900 SH SOLE SOLE
Prime Bancorp Common 741914105 893 35,800 SH SOLE SOLE
Station Casinos Common 857689103 710 55,700 SH SOLE SOLE
Sundstrand Corp. Common 867323107 10,800 155,400 SH SOLE SOLE
Sybron Chemical Common 870903101 2,521 197,700 SH SOLE SOLE
The Learning Co. Common 522008101 36,784 1,268,400 SH SOLE SOLE
Thermadyne Holding Common 883435208 416 26,004 SH SOLE SOLE
Transamerica Corp. Common 893485102 3,550 50,000 SH SOLE SOLE
U.S. Filter Common 911843209 23,064 753,100 SH SOLE SOLE
U.S. Office Products Common 912325305 1,576 393,909 SH SOLE SOLE
Unihost Common 904922101 157 37,500 SH SOLE SOLE
US Satellite Broad. Common 912534104 1,826 106,600 SH SOLE SOLE
Vanguard Cellular Common 922022108 17,232 630,924 SH SOLE SOLE
Varian Associates Common 92220p105 14,252 367,800 SH SOLE SOLE
VLSI Technology Common 918270109 10,260 527,000 SH SOLE SOLE
Whittaker Corp. Common 966680407 3,115 142,000 SH SOLE SOLE
Workflow Mgmt. Common 98137n109 4,188 620,430 SH SOLE SOLE
XTRA Corp. Common 984138107 6,356 165,900 SH SOLE SOLE
Xylan Corp. Common 984151100 27,168 738,000 SH SOLE SOLE
Young Broadcasting Common 987434107 707 15,500 SH SOLE SOLE
YPF Sociodad Common 984245100 1,105 35,000 SH SOLE SOLE
Fresenius Pfd. Preferred 358030203 33 1,665,173 SH SOLE SOLE
</TABLE>
