Filed pursuant to Rule 424 (b)(3)
Registration No. 333-76546
3,000,000 SHARES
OF
CHESAPEAKE ENERGY CORPORATION
6.75% CUMULATIVE CONVERTIBLE PREFERRED STOCK
(LIQUIDATION PREFERENCE $50 PER SHARE)
AND
COMMON STOCK,
(PAR VALUE $.01 PER SHARE)
PROSPECTUS SUPPLEMENT NO. 12
DATED OCTOBER 7, 2003
TO PROSPECTUS DATED JANUARY 30, 2002
-------------------
The selling securityholders table on page 27 and 28 of the prospectus
is amended by this supplement no.12 to read as follows.
NUMBER OF
NUMBER OF NUMBER OF SHARES OF
SHARES OF NUMBER OF SHARES OF NUMBER OF NUMBER OF COMMON STOCK
PREFERRED SHARES OF PREFERRED SHARES OF SHARES OF TO BE OWNED
STOCK PREFERRED STOCK TO BE COMMON STOCK COMMON AFTER
BENEFICIALLY STOCK BEING OWNED AFTER BENEFICIALLY STOCK BEING COMPLETION
OWNED PRIOR OFFERED COMPLETION OWNED PRIOR TO OFFERED OF THE
NAME TO THE OFFERING HEREBY OF THE OFFERING THE OFFERING HEREBY OFFERING
---- ---------------------------------------------------------------------------------------
AIG Soundshore Holdings Ltd... 139,500 139,500 0 905,843 905,843 0
AIG Soundshore Opportunity
Holding Fund Ltd............ 76,400 76,400 0 496,103 496,103 0
AIG Soundshore Strategic
Holding Fund Ltd............ 46,100 46,100 0 299,350 299,350 0
Alpine Associates............. 100,000 100,000 0 649,350 649,350 0
Alpine Partners, L.P.......... 15,000 15,000 0 97,403 97,403
American Samoa Government..... 1,000 1,000 0 6,494 6,494 0
Argent Classic Convertible
Arbitrage Fund (Bermuda) Ltd.. 10,000 10,000 0 64,935 64,935 0
Argent Classic Convertible
Arbitrage Fund L.P............ 15,000 15,000 0 97,403 97,403 0
Argent LowLev Convertible
Arbitrage Fund Ltd.......... 33,000 33,000 0 214,286 214,286 0
Banc of America Securities LLC 180,000 180,000 0 1,168,830 1,168,830 0
Bear, Stearns & Co. Inc....... 5,000 5,000 0 32,468 32,468 0
BGI Global Investors
c/o Forest Investment Mngt. 6,200 6,200 0 40,260 40,260 0
L.L.C
BP Amoco PLC Master Trust..... 24,130 24,130 0 156,688 156,688 0
CF FX, LLC.................... 62,000 62,000 0 402,597 402,597 0
Credit Suisse First Boston
Corporation................... 128,500 128,500 0 834,415 834,415 0
CSFB Convertible and
Quantitative Strategies..... 50,000 50,000 0 324,675 324,675 0
Fidelity Financial Trust:
Fidelity Convertible
Securities 405,000 405,000 0 2,629,868 2,629,868 0
Fund........................
First Union National Bank..... 295,000 295,000 0 1,915,583 1,915,583 0
FIST - Franklin Convertible
Securities Fund............. 40,000 40,000 0 259,740 259,740 0
Forest Alternative Strategies II 1,800 1,800 0 11,688 11,688 0
Forest Fulcrum Fund L.L.P..... 20,000 20,000 0 129,870 129,870 0
Forest Global Convertible Fund
Series A-5.................. 75,600 75,600 0 490,909 490,909 0
Franklin Custodian Fund -
Income Fund................. 270,800 270,800 0 1,758,440 1,758,440 0
FTIF - Franklin Income Fund... 1,000 1,000 0 6,494 6,494 0
FTVIPT - Franklin Income
Securities Fund............. 18,000 18,000 0 116,883 116,883 0
Global Bermuda Limited
Partnership................. 4,000 4,000 0 25,974 25,974 0
HFR TQA Master Trust.......... 10,000 10,000 0 64,935 64,935 0
Highbridge International LLC.. 10,000 10,000 0 64,935 64,935 0
Hotel Union & Hotel Industry of 10,700 10,700 0 69,480 69,480 0
Hawaii Pension Plan...........
Jefferies & Co................ 88,000 88,000 0 571,428 571,428 0
Jefferies and Company, Inc.
c/o SSI Investment Management
Inc......................... 235 235 0 1,526 1,526 0
KBC Financial Products USA Inc. 17,500 17,500 0 113,636 113,636 0
Lakeshore International Ltd... 16,000 16,000 0 103,896 103,896 0
Lazard Freres & Co. LLC....... 76,700 76,700 0 498,051 498,051 0
LDG Limited................... 10,000 10,000 0 64,935 64,935 0
Lipper Convertibles, L.P...... 150,000 150,000 0 974,025 974,025 0
LLT Limited................... 6,200 6,200 0 40,260 40,260 0
Lyxor Master Fund Ref:
Argent/LowLev CB
c/o Argent................... 10,000 10,000 0 64,935 64,935 0
Lyxor Master Fund............. 2,000 2,000 0 12,987 12,987 0
Navigator Offshore Fund, Ltd.. 15,000 15,000 0 97,403 97,403 0
Navigator Partners L.P........ 3,000 3,000 0 19,481 19,481 0
Onex Industrial Partners Limited 7,250 7,250 0 47,078 47,078 0
Pebble Capital Inc............ 3,000 3,000 0 19,481 19,481 0
Peoples Benefit Life Insurance
Company/TEAMSTERS........... 17,500 17,500 0 113,636 113,636 0
Ramius Capital Group.......... 10,000 10,000 0 64,935 64,935 0
RBC Capital Services Inc.
c/o Forest Investment Mngt.
LLC......................... 1,500 1,500 0 9,740 9,740 0
RCG Halifax Master Fund Ltd... 5,000 5,000 0 32,468 32,468 0
RCG Latitude Master Fund Ltd.. 15,000 15,000 0 97,403 97,403 0
RCG Multi Strategy LP......... 10,000 10,000 0 64,935 64,935 0
Retail Clerks Pension Trust #2 17,500 17,500 0 113,636 113,636 0
Silvercreek II Limited........ 9,750 9,750 0 63,312 63,312 0
Silvercreek Limited Partnership 5,000 5,000 0 32,468 32,468 0
Speer, Leeds & Kellogg L.P.... 10,000 10,000 0 64,935 64,935 0
Sunrise Partners LLC.......... 269,000 269,000 0 1,746,752 1,746,752 0
Sylvan (IMA) Ltd.
c/o Forest Investment Mngt.
L.L.C....................... 7,500 7,500 0 48,701 48,701 0
The Estate of James Campbell.. 3,249 3,249 0 21,097 21,097 0
The James Campbell Corporation 4,291 4,291 0 27,864 27,864 0
The Northwestern Mutual Life
Insurance Company........... 30,000 30,000 0 194,805 194,805 0
TQA Master Fund, LTD.......... 50,000 50,000 0 324,675 324,675 0
TQA Master Plus Fund LTD...... 45,000 45,000 0 292,208 292,208 0
UBS O'Connor LLC F/B/O
UBS Global Equity
Arbitrage Master Ltd........ 70,000 70,000 0 454,545 454,545 0
Viacom Inc.
Pension Plan Master Trust... 960 960 0 6,234 6,234 0
White River Securities L.L.C.. 5,000 5,000 0 32,468 32,468 0
Yield Strategies Fund I, LP... 7,500 7,500 0 48,701 48,701 0
Yield Strategies Fund II, LP.. 7,500 7,500 0 48,701 48,701 0
Zurich Institutional Benchmarks
Master Fund
c/o TQA Investors, L.L.C.... 10,000 10,000 0 64,935 64,935 0
Zurich Institutional Benchmarks
Master Fund Ltd............... 20,435 20,435 0 132,695 132,695 0
Zurich Master Hedge Fund
c/o Forest Investment Mngt.
L.L.C....................... 6,200 6,200 0 40,260 40,260 0
(1) The stated amounts, to the extent they describe common stock issuable upon
conversion of the holder's preferred stock, assume conversion of all of the
holders' preferred stock at a conversion ratio of 6.4935 shares of our
common stock per share of preferred stock. This conversion ratio, however,
will be subject to adjustment as described under "Description of the
Preferred Stock - Conversion Price Adjustment". As a result, the number of
shares of our common stock issuable upon conversion of the preferred stock
and, therefore, attributable to holders of preferred stock, may increase or
decrease in the future.
2