SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  SCHEDULE 13D
                               (Amendment No. 3)*

                    Under the Securities Exchange Act of 1934

                          CHESAPEAKE ENERGY CORPORATION
                                (Name of Issuer)

                          Common Stock, par value $.01
                         (Title of Class of Securities)

                                   165167 10 7
                                 (CUSIP Number)

                              Shannon Self, Esquire
                           Commercial Law Group, P.C.
                               2725 Oklahoma Tower
                                 210 Park Avenue
                          Oklahoma City, Oklahoma 73102
                                 (405) 232-3001
                  (Name, Address and Telephone Number of Person
                Authorized to Receive Notices and Communications)

                                  May 30, 2003
             (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 Rule 13d-1(e),  Rule 13d-1(f) or Rule  13d-1(g),  check the
following box. [ ]

Note:  Schedules  filed in paper format shall include a signed original and five
copies of the  schedule,  including  all  exhibits.  See Rule 13d-7(b) for other
parties to whom copies are to be sent.

* 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
disclosures provided in a prior cover page.

The information required on 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).






CUSIP NO. 16517 10 7


  (1)   Names of Reporting Persons, I.R.S. Identification   Aubrey K. McClendon
        Nos. of Above Persons (entities only)

  (2)   Check the Appropriate Box if a Member of a Group               (a)  [x]
        (See Instructions)                                             (b)  [ ]

  (3)   SEC Use Only

  (4)   Source of Funds (See Instructions)                                   PF

  (5)   Check if Disclosure of Legal Proceedings is Required                [ ]
        Pursuant to Items 2(d) or 2(e)

  (6)   Citizenship or Place of Organization                                USA

        -----------------------------------------------------

Number of Shares     (7)   Sole Voting Power                         13,777,383

Beneficially Owned   (8)   Shared Voting Power                           13,560

By Each Reporting    (9)   Sole Disposition                          13,777,383

Person With:        (10)  Shared Dispositive Power                       13,560


 (11)   Aggregate Amount Beneficially Owned by Each                  13,790,943
        Reporting Person

 (12)   Check if the Aggregate Amount in Row (11) Excludes Certain          [x]
        Certain Shares (See Instructions)

 (13)   Percent of Class Represented by Amount in Row (11)                6.31%

 (14)   Type of Reporting Person (See Instructions)                          IN


                                       2


CUSIP NO. 16517 10 7


  (1)   Names of  Reporting  Persons, I.R.S.       Chesapeake Investments, an
        Identification                             Oklahoma Limited Partnership
        Nos.  of Above Persons (entities only)     Oklahoma Limited Partnership
                                                                     73-1132104

  (2)   Check the Appropriate Box if a Member of a Group                 (a)[x]
        (See Instructions)                                               (b)[ ]

  (3)   SEC Use Only

  (4)   Source of Funds (See Instructions)                                  N/A

  (5)   Check if Disclosure of Legal Proceedings is                         [ ]
        Required Pursuant to Items 2(d) or 2(e)

  (6)   Citizenship or Place of Organization                           Oklahoma

        ------------------------------------------------------

Number of Shares     (7)   Sole Voting Power                                  0

Beneficially Owned   (8)   Shared Voting Power                           13,560

By Each Reporting    (9)   Sole Disposition                                   0

Person With:        (10)   Shared Dispositive Power                      13,560


 (11)   Aggregate Amount Beneficially Owned by Each                      13,560
        Reporting Person

(12)    Check if the Aggregate Amount in Row (11)                           [x]
        Excludes Certain Shares (See Instructions)

(13)    Percent of Class Represented by Amount in Row (11)                0.01%

(14)    Type of Reporting Person (See Instructions)                          PN


                                       3


CUSIP NO. 16517 10 7


  (1)   Names of Reporting Persons, I.R.S. Identification           Tom L. Ward
        Nos. of Above Persons (entities only)

  (2)   Check the Appropriate Box if a Member of a Group                 (a)[x]
        (See Instructions)                                               (b)[ ]

  (3)   SEC Use Only

  (4)   Source of Funds (See Instructions)                                   PF

  (5)   Check if Disclosure of Legal Proceedings                            [ ]
        is Required Pursuant to Items 2(d) or 2(e)

  (6)   Citizenship or Place of Organization                                USA

        ------------------------------------------------------------

Number of Shares     (7)   Sole Voting Power                         14,027,576

Beneficially Owned   (8)   Shared Voting Power                        1,153,510

By Each Reporting    (9)   Sole Disposition                          14,027,576

Person With:        (10)   Shared Dispositive Power                   1,153,510


(11)    Aggregate Amount Beneficially Owned by Each                  15,181,086
        Reporting Person

(12)    Check if the Aggregate Amount in Row (11)                           [x]
        Excludes Certain Shares (See Instructions)

(13)    Percent of Class Represented by Amount in Row (11)                6.89%

(14)    Type of Reporting Person (See Instructions)                          IN


                                       4



CUSIP NO. 16517 10 7


 (1)    Names of Reporting Persons, I.R.S. Identification  TLW Investments Inc.
        Nos. of Above Persons (entities only)                        73-1215253

 (2)    Check the Appropriate Box if a Member of a Group                 (a)[x]
        (See Instructions)                                               (b)[ ]

  (3)    SEC Use Only

  (4)    Source of Funds (See Instructions)                                   WC

  (5)    Check if Disclosure of Legal Proceedings is                        [ ]
         Required Pursuant
           to Items 2(d) or 2(e)

  (6)    Citizenship or Place of Organization                          Oklahoma

         ----------------------------------------------------------

Number of Shares     (7)   Sole Voting Power                                  0

Beneficially Owned   (8)   Shared Voting Power                        1,153,510

By Each Reporting    (9)   Sole Disposition                                   0

Person With:        (10)   Shared Dispositive Power                   1,153,510


 (11)    Aggregate Amount Beneficially Owned by Each                  1,153,510
         Reporting Person

 (12)    Check if the Aggregate Amount in Row (11)                          [x]
         Excludes Certain Shares (See Instructions)

 (13)    Percent of Class Represented by Amount in Row (11)               0.54%

 (14)    Type of Reporting Person (See Instructions)                         CO



                                       5


CUSIP NO. 16517 10 7


                              Preliminary Statement

This  Amendment  No. 3 to  Schedule  13D  updates:  (a) the  Schedule  13D dated
February 4, 1993,  and filed by the group  consisting of Aubrey K. McClendon and
Chesapeake Investments, an Oklahoma Limited Partnership ("CI"); (b) the Schedule
13D dated February 4, 1993, and filed by the group consisting of Tom L. Ward and
TLW Investments Inc. ("TLW"); (c) Amendment No. 1 to Schedule 13D filed on March
10,  1997,  by the  group  consisting  of Mr.  McClendon  and CI and  the  group
consisting of Mr. Ward and TLW; and (d) Amendment No. 2 to Schedule 13D filed on
December 2, 1999, by the group  consisting of Mr. McClendon and CI and the group
consisting  Mr.  Ward and TLW  (collectively,  the "Prior  Schedule  13D").  Mr.
McClendon,  CI,  Mr.  Ward and TLW are  referred  to  herein  as the  "Reporting
Persons." The group  consisting of Mr. McClendon and CI and the group consisting
of Mr. Ward and TLW each disclaim beneficial ownership of the shares held by the
other group.

Item 1.  Security and Issuer.

         This  Schedule  13D  relates to the common  stock,  par value $0.01 per
         share (the  "Common  Stock"),  of  Chesapeake  Energy  Corporation,  an
         Oklahoma  corporation  (the "Company")  having its principal  executive
         offices at 6100 North Western Avenue, Oklahoma City, Oklahoma 73118.

Item 2.  Identity and Background.

         (a)-(c)

         Aubrey K. McClendon

         Mr. McClendon is the Chairman of the Board and Chief Executive  Officer
         of the Company, having a business address of 6100 North Western Avenue,
         Oklahoma City,  Oklahoma  73118.  The Company is engaged in oil and gas
         exploration and development.

         Chesapeake Investments

         Chesapeake Investments, an Oklahoma Limited Partnership, is an Oklahoma
         limited  partnership,  having a business  address of 6100 North Western
         Avenue,  Oklahoma  City,  Oklahoma  73118.  Mr.  McClendon  is the sole
         general  partner of CI. CI is  principally  engaged in the ownership of
         working interests in oil and gas wells and leases.

         Tom L. Ward

         Mr. Ward is the President and Chief  Operating  Officer of the Company,
         having a business address of 6200 North Western Avenue,  Oklahoma City,
         Oklahoma 73118.


                                       6


CUSIP NO. 16517 10 7


         TLW Investments Inc.

         TLW  Investments  Inc., is an Oklahoma  corporation  having a business
         address of 6200 North Western Avenue,  Oklahoma City,  Oklahoma 73118.
         Mr. Ward is the sole shareholder,  director, and president of TLW. TLW
         is  principally  engaged in the ownership of working  interests in oil
         and gas wells and leases.

         (d)  During  the past  five  (5)  years no  Reporting  Person  has been
         convicted in a criminal  proceeding  (excluding  traffic  violations or
         similar misdemeanors).

         (e)  During the past five (5) years,  no  Reporting  Person has been a
         party to a civil proceeding of a judicial or an administrative body of
         competent  jurisdiction as a result of which a Reporting Person is, or
         was,  subject to a judgment,  decree or final order  enjoining  future
         violations  of, or  prohibiting  or  mandating  activity  subject  to,
         federal or state securities laws or finding any violation with respect
         to such laws.

         (f)  Each of Mr. McClendon and Mr. Ward is a citizen of the United
         States.

Item 3.  Source and Amount of Funds or Other Consideration.

         The Reporting  Persons acquired more than 5% of the outstanding  Common
         Stock of the  Company  upon the  formation  and  capitalization  of the
         Company  effective  January 1, 1992. As the primary  consideration  for
         such shares,  the Reporting Persons conveyed to the Company certain oil
         and  gas  properties,   stock  of  various  corporations  which  became
         wholly-owned  subsidiaries  of the  Company,  other real  property  and
         personal  property.  Subsequent  to the  formation of the Company,  the
         Reporting  Persons  acquired  or  disposed  of shares of the  Company's
         common  stock  through  open market  transactions,  acquired  shares of
         Common Stock through  issuances  under the Company's  benefit plans and
         acquired  shares of Common Stock  through  exercises of employee  stock
         options  issued to Mr.  McClendon  and Mr.  Ward  under  the  Company's
         employee  stock option plans.  Each  acquisition  or disposition of the
         Common Stock was reported on Form 4 or 5 in  accordance  with the rules
         promulgated by the Securities and Exchange  Commission under Section 16
         of the Securities Exchange Act of 1934.

         Since the filing of the Prior  Schedule  13D,  Mr.  McClendon  has: (a)
         purchased  739,350  shares  of  Common  Stock  in the open  market  for
         aggregate  consideration of $5.59 million; (b) purchased 133,333 shares
         of Common Stock through the Company's  public  offering of common stock
         on December 18, 2002 for  aggregate  consideration  of $1 million;  (c)
         purchased  123,457 shares of Common Stock through the Company's  public
         offering on March 5, 2003 for  aggregate  consideration  of $1 million;
         (d) acquired  1.88 million  shares of Common Stock through the exercise
         of employee  stock  options for an  aggregate  exercise  price of $2.56
         million satisfied through the surrender of 0.4 million shares of Common
         Stock owned by him;  and (e)  acquired  25,789  shares of Common  Stock
         under the Company's benefit plans. The foregoing  purchases were funded
         through the expenditure of Mr. McClendon's personal funds. In addition,
         Mr.  McClendon has  purchased  237,750  shares of the  Company's  6.75%
         Cumulative  Convertible  Preferred Stock, par value $0.01 per share and
         liquidation  preference  $50 per share  ("Preferred  Stock"),  which is
         convertible  at any time by Mr.  McClendon  into  1,543,830  shares  of
         Common  Stock.  The aggregate  purchase  price of $18 million for these
         shares was paid from Mr. McClendon's personal funds.

                                       7

CUSIP NO. 16517 10 7


         Since the filing of the Prior Schedule 13D, Mr. Ward has: (a) purchased
         674,000  shares  of  Common  Stock in the  open  market  for  aggregate
         consideration of $5.3 million;  (b) purchased  133,333 shares of Common
         Stock  through the Company's  public  offering on December 18, 2002 for
         aggregate  consideration  of $1 million;  (c) purchased  123,457 shares
         through the  Company's  public  offering on March 5, 2003 for aggregate
         consideration of $1 million; (d) acquired 76,500 shares of Common Stock
         through  the  exercise  of  employee  stock  options  for an  aggregate
         exercise  price of $0.1  million;  and (e)  acquired  25,396  shares of
         Common Stock under the Company's benefit plans. The foregoing purchases
         were funded through the  expenditure of Mr. Ward's  personal  funds. In
         addition,  Mr. Ward has  purchased  237,750  shares of Preferred  Stock
         which is convertible  at any time by Mr. Ward into 1,543,830  shares of
         Common  Stock.  The aggregate  purchase  price of $18 million for these
         shares was paid from Mr. Ward's personal funds.

         Since the filing of the Prior  Schedule 13D, TLW  Investments  Inc. has
         purchased  309,350  shares  of  Common  Stock  in the open  market  for
         aggregate  consideration  of  $2.2  million  using  that  corporation's
         working capital.

Item 4.  Purpose of Transaction.

         Mr.  McClendon  and Mr. Ward  acquired  the shares of Common  Stock and
         Preferred Stock for investment  purposes and are currently  inclined to
         purchase  additional  shares  depending  on a number of factors such as
         price and industry  trends.  Thus, in the future the Reporting  Persons
         may purchase  additional shares of Common Stock or Preferred Stock, but
         may also dispose of any or all of the Common  Stock or Preferred  Stock
         in any manner  permitted by applicable  securities  laws. Mr. McClendon
         and Mr. Ward are each members of the  Company's  Board of Directors and
         as such may  participate  as a director  in  decisions  by the Board of
         Directors  enumerated  in  paragraphs  (a) through (j) of Item 4. Other
         than Mr.  McClendon's  and Mr.  Ward's  participation  on the  Board of
         Directors and except as otherwise disclosed in this Item 4, none of the
         Reporting  Persons has any present plans or intentions  relating to the
         transactions described in paragraphs (a) through (j) of Item 4.

Item 5.  Interest in Securities of the Issuer.

         The  aggregate  percentage  of  shares  of  Common  Stock  reported  as
         beneficially  owned by each  Reporting  Person was computed  based upon
         214,478,465 shares of Common Stock outstanding on May 30, 2003.

         (a) The following  table sets forth the aggregate  number of shares and
         percentage  of the Common Stock  beneficially  owned by each  Reporting
         Person:

              Person                    Amount            Percent
              ------                    ------            -------

        Aubrey K. McClendon         13,790,943 (1)(2)       6.31%

        Chesapeake Investments      13,560 (2)              0.01%

        Tom L. Ward                 15,181,086 (3)(4)       6.89%

        TLW Investments             1,153,510 (4)           0.54%

     --------------------

                                       8


CUSIP NO. 16517 10 7


(1) This amount  includes:  (i) 90,760 shares held on behalf of Mr. McClendon in
the Chesapeake  Energy  Corporation  Savings and Incentive  Stock Bonus Plan and
8,612  shares  held  on  behalf  of  Mr.  McClendon  in  the  Chesapeake  Energy
Corporation  401(k) Make-Up Plan (which are subject to a number of  restrictions
and vesting  provisions) as of March 31, 2003, the latest date such  information
is available; (ii) 2,590,857 shares which Mr. McClendon has the right to acquire
within sixty (60) days  pursuant to stock  options  granted by the Company;  and
(iii) 1,543,830 shares which Mr. McClendon has the right to acquire within sixty
(60) days upon conversion of Preferred Stock.

(2) This  amount  includes  13,560  shares  owned of  record by CI, of which Mr.
McClendon is the sole general  partner.  CI and Mr.  McClendon  share voting and
dispositive power over such shares.

(3) This  amount  includes  (i) 43,286  shares held on behalf of Mr. Ward in the
Chesapeake Energy  Corporation  Savings and Incentive Stock Bonus Plan and 8,612
shares held on behalf of Mr. Ward in the Chesapeake  Energy  Corporation  401(k)
Make-Up  Plan  (which  are  subject  to a number  of  restrictions  and  vesting
provisions) as of March 31, 2003, the latest date such information is available;
(ii) 4,390,808  shares which Mr. Ward has the right to acquire within sixty (60)
days pursuant to stock options granted by the Company;  (iii)  1,543,830  shares
which Mr. Ward has the right to acquire  within sixty (60) days upon  conversion
of  Preferred  Stock;  and (iv)  21,435  shares  held by Mr.  Ward in  custodial
accounts for the benefit of Mr. Ward's children.

(4) This amount includes  1,153,510  shares owned of record by TLW, of which Mr.
Ward is the sole shareholder, director, and Chief Executive Officer. TLW and Mr.
Ward share voting and dispositive power over such shares.

(b) The  following  table sets forth the number of shares of Common Stock of the
Company for which each Reporting Person has (1) the sole power to vote or direct
the voting, (2) shared power to vote or direct the voting, (3) the sole power to
dispose  or to direct  the  disposition,  or (4)  shared  power to dispose or to
direct the disposition:


                              Sole Voting and           Shared Voting and
 Person or Entity           Power of Disposition      Power of Disposition

Aubrey K. McClendon            13,777,383 (1)               13,560 (2)

Chesapeake Investments                  0                   13,560 (2)

Tom L. Ward                    14,027,576 (3)            1,153,510 (4)

TLW Investments                         0                1,153,510 (4)

----------------------

(1) See footnote (1) under paragraph (a) of this Item 5.

(2) See footnote (2) under paragraph (a) of this Item 5.

(3) See footnote (3) under paragraph (a) of this Item 5.

(4) See footnote (4) under paragraph (a) of this Item 5.

(c) During the sixty days prior to the date of this  Schedule 13D, the following
transactions were effected in the Common Stock by the Reporting Persons:

                                       9


CUSIP NO. 16517 10 7


From May 1, 2003 through May 12, 2003, Mr. McClendon  purchased shares of Common
Stock on the open market as follows:


                    ------------------ -------------- ---------------------
                          Date            Shares        Price per Share
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03          4,000         $8.18
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03         30,000         $8.20
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03         50,000         $8.21
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03         41,000         $8.22
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/2/03         20,000         $8.30
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/6/03         30,000         $8.70
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/8/03         20,000         $8.75
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/9/03         25,000         $8.95
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         3,500         $9.16
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         1,650         $9.17
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03        17,700         $9.19
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03        32,450         $9.20
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         5,700         $9.22
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         4,350         $9.23
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         4,950         $9.24
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03        39,050         $9.25
                    ------------------ -------------- ---------------------


                                       10


CUSIP NO. 16517 10 7


From May 1, 2003 through May 6, 2003, Mr. Ward purchased  shares of Common Stock
on the open market as follows:

                    ------------------ -------------- ---------------------
                          Date            Shares        Price per Share
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03          4,000         $8.18
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03         30,000         $8.20
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03         50,000         $8.21
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/1/03         41,000         $8.22
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/2/03         20,000         $8.30
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/5/03            500         $8.58
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/5/03         60,000         $8.59
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/5/03         55,500         $8.60
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/6/03         20,000         $8.65
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/6/03          5,200         $8.66
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/6/03         36,500         $8.69
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/6/03         53,300         $8.70
                    ------------------ -------------- ---------------------


On May 12, 2003, TLW Investments  Inc.  purchased  shares of Common Stock on the
open market as follows:


                    ------------------ -------------- ---------------------
                          Date            Shares        Price per Share
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         3,500        $9.16
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         1,650        $9.17
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03       17,700         $9.19
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03       32,450         $9.20
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         5,700        $9.22
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         4,350        $9.23
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03         4,950        $9.24
                    ------------------ -------------- ---------------------
                    ------------------ -------------- ---------------------
                         5/12/03       39,050         $9.25
                    ------------------ -------------- ---------------------


                                       11



CUSIP NO. 16517 10 7


From May 14,  2003  through  May 30,  2003,  Mr.  McClendon  and Mr.  Ward  each
purchased 237,750 shares of Preferred Stock on the open market as follows:


------------- ------------- ------------ ------------- ------------ -----------
                McClendon      Common         Ward         Common     Price per
  Date           Shares      Equivalent      Shares      Equivalent   Preferred
                                                                        Share
------------- ------------- ------------ ------------- ------------ -----------
------------- ------------- ------------ ------------- ------------ -----------
 5/14/03        50,000         324,675       50,000       324,675        $72.12
------------- ------------- ------------ ------------- ------------ -----------
------------- ------------- ------------ ------------- ------------ -----------
 5/16/03           500           3,247          500         3,247        $73.51
------------- ------------- ------------ ------------- ------------ -----------
------------- ------------- ------------ ------------- ------------ -----------
 5/16/03        25,000         162,338       25,000       162,338        $73.99
------------- ------------- ------------ ------------- ------------ -----------
------------- ------------- ------------ ------------- ------------ -----------
 5/20/03        35,000         227,273       35,000       227,273        $73.63
------------- ------------- ------------ ------------- ------------ -----------
------------- ------------- ------------ ------------- ------------ -----------
 5/22/03        71,000         461,039       71,000       461,039        $77.72
------------- ------------- ------------ ------------- ------------ -----------
------------- ------------- ------------ ------------- ------------ -----------
 5/23/03        30,000         194,805       30,000       194,805        $77.64
------------- ------------- ------------ ------------- ------------ -----------
------------- ------------- ------------ ------------- ------------ -----------
  5/30/03       26,250         170,454       26,250       170,454        $77.654
------------- ------------- ------------ ------------- ------------ -----------

Each share of Preferred  Stock is  convertible  at any time at the option of the
holder into 6.4935 shares of Common Stock.

(d) See Item 6, below.

(e) Not applicable.

Item 6. Contracts,  Agreements,  Underwritings or Relationships  With Respect to
Securities of the Issuer.

         Mr. McClendon and Mr. Ward, as officers of the Company, are eligible to
         participate  in the Company's 1992  Incentive  Stock Option Plan,  1992
         Nonstatutory  Stock  Option Plan,  as amended,  1994 Stock Option Plan,
         1996 Stock Option Plan, 1999 Stock Option Plan, 2000 Executive  Officer
         Stock Option Plan,  2000  Employee  Stock Option Plan,  2001  Executive
         Officer Stock Option Plan,  2001 Stock Option Plan,  2001  Nonqualified
         Stock Option Plan,  2002 Stock Option  Plan,  2002  Nonqualified  Stock
         Option Plan, 2003 Stock Incentive Plan and 401(k) Make-Up Plan.

         Mr. McClendon  maintains  lending  arrangements with RBC Dain Rauscher,
         Inc. ("RBC") as successor to Rauscher,  Pierce & Refnes, Inc., pursuant
         to an agreement  dated February 25, 1994 and with Goldman,  Sachs & Co.
         ("Goldman") pursuant to an agreement dated July 11, 2002. Mr. McClendon
         and CI have pledged 2.66 million  shares of Common as collateral  for a
         loan with RBC and 6.15  million  shares of Common  Stock are  currently
         pledged as collateral for a loan with Goldman.  The agreements  contain
         standard default and remedial provisions.

         Mr.  Ward  maintains  lending  arrangements  with  RBC  Dain  Rauscher,
         pursuant to an agreement  dated May 9, 2000 and with  Goldman,  Sachs &
         Co.  pursuant to an agreement dated July 11, 2002. TLW has pledged 1.15
         million  shares of Common Stock as  collateral  for a loan with RBC and
         6.0  million  shares of Common  Stock  currently  owned by Mr. Ward are
         pledged as collateral for a loan with Goldman.  The agreements  contain
         standard default and remedial provisions.

         In  connection  with a loan  from  Frederick  B.  Whittemore:  (a)  Mr.
         McClendon  granted to Mr.  Whittemore,  pursuant to that certain Common
         Stock  Purchase  Option  dated  March 10,  1999,  an option to purchase
         394,688  shares of Common Stock at a purchase price of $0.50 per share;
         and (b) Mr.  Ward  granted  to Mr.  Whittemore  an option  to  purchase
         355,312  shares of Common Stock at a purchase price of $0.50 per share.
         The option expires August 31, 2006.

         The shares of  Preferred  Stock  reported  herein have been  pledged as
         security for the performance of financial obligations Mr. McClendon and
         Mr.  Ward  may  have  from  time to time  pursuant  to  energy  trading
         transactions with  Kaiser-Francis Oil Company.  As a result, the shares
         may be subject  to  transfer  if there is a default in the  obligations
         secured by the parties' oral pledge agreement.



                                       12



CUSIP NO. 16517 10 7


Item 7.  Materials to be Filed as Exhibits.

 1.      Limited Partnership  Agreement of Chesapeake  Investments,  an Oklahoma
         Limited  Partnership,  is filed as Exhibit E to the  Schedule 13D dated
         February  4,  1993  filed by Aubrey K.  McClendon  and is  incorporated
         herein by reference.

 2.      The  Company's  1992  Incentive  Stock  Option  Plan,  as  amended,  is
         incorporated  herein by  reference to Exhibit  10.1.1 to the  Company's
         Registration Statement on Form S-4, No. 33-93718.

 3.      The  Company's  1992  Nonstatutory  Stock Option Plan,  as amended,  is
         incorporated  herein by  reference to Exhibit  10.1.2 to the  Company's
         Quarterly Report on Form 10-Q for the quarter ended December 31, 1996.

 4.      The  Company's  1994  Stock  Option  Plan  is  incorporated  herein  by
         reference to Exhibit 10.1.3 to the Company's  Quarterly  Report on Form
         10-Q for the quarter ended December 31, 1996.

 5.      The  Company's  1996  Stock  Option  Plan  is  incorporated  herein  by
         reference to Exhibit B to the Company's  definitive proxy statement for
         its 1996 annual meeting of shareholders filed November 6, 1996 .

 6.      The  Company's  1999  Stock  Option  Plan  is  incorporated  herein  by
         reference to Exhibit 10.1.5 to the Company's  quarterly  report on Form
         10-Q for the quarter ended June 30, 1999.

 7.      The Company's 2000 Employee Stock Option Plan is incorporated herein by
         reference to Exhibit 10.1.6 to the Company's  quarterly  report on Form
         10-Q for the quarter ended March 31, 2000.

 8.      The Company's 2000 Executive  Officer Stock Option Plan is incorporated
         herein by reference to Exhibit 10.1.7 to the Company's quarterly report
         on Form 10-Q for the quarter ended March 31, 2000.

 9.      The  Company's  2001  Stock  Option  Plan  is  incorporated  herein  by
         reference to Exhibit B to the Company's  definitive proxy statement for
         its 2001 annual meeting of shareholders filed April 30, 2001.

10.      The Company's 2001 Executive  Officer Stock Option Plan is incorporated
         herein by reference to Exhibit 10.1.9 to the Company's quarterly report
         on Form 10-Q for the quarter ended June 30, 2001.

11.      The  Company's  2001  Nonqualified  Stock  Option Plan is  incorporated
         herein by  reference  to  Exhibit  10.1.10 to the  Company's  quarterly
         report on Form 10-Q for the quarter ended June 30, 2001.

12.      The  Company's  2002  Stock  Option  Plan  is  incorporated  herein  by
         reference to Exhibit A to the Company's  definitive proxy statement for
         its 2002 annual meeting of shareholders filed April 29, 2002.

13.      The  Company's  2002  Nonqualified  Stock  Option Plan is  incorporated
         herein by  reference  to  Exhibit  10.1.11 to the  Company's  quarterly
         report on Form 10-Q for the quarter ended June 30, 2002.

14.      The  Company's  2003 Stock  Incentive  Plan is  incorporated  herein by
         reference to Exhibit A to the Company's  definitive proxy statement for
         its 2003 annual meeting of shareholders filed April 17, 2003.

15.      The Company's  401(k) Make-Up Plan is incorporated  herein by reference
         to Exhibit 10.1.15 to the Company's  annual report on Form 10-K for the
         year ended December 31, 2002.

16.      Common Stock Purchase  Option No. AKM-1 dated March 10, 1999,  executed
         by Aubrey K. McClendon in favor of Frederick B. Whittemore was filed as
         Exhibit 13 to Amendment  No. 2 to Schedule  13D filed by the  Reporting
         Persons on December 2, 1999 and is incorporated herein by reference.

17.      Common Stock Purchase  Option No. TLW-1 dated March 10, 1999,  executed
         by Tom L. Ward in favor of Frederick B. Whittemore was filed as Exhibit
         14 to Amendment No. 2 to Schedule 13D filed by the Reporting Persons on
         December 2, 1999 and is incorporated herein by reference.

18.      Joint Filing Agreement.


                                       13



CUSIP NO. 16517 10 7


                                                      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.

DATED:   June 17, 2003.

                                           /s/ Aubrey K. McClendon
                                           ------------------------------------
                                           AUBREY K. McCLENDON, an individual

                                           CHESAPEAKE INVESTMENTS, an Oklahoma
                                           Limited Partnership

                                       By: /s/ Aubrey K. McClendon
                                           ------------------------------------
                                           Aubrey K. McClendon, General Partner


                                           /s/ Tom L. Ward
                                           ------------------------------------
                                           TOM L. WARD, an individual

                                           TLW INVESTMENTS INC., an Oklahoma
                                           corporation

                                       By: /s/ Tom L. Ward
                                           ------------------------------------
                                               Tom L. Ward, President



                                       14



CUSIP NO. 16517 10 7


                                INDEX TO EXHIBITS


Exhibit
  No.       Description                                      Method of Filing

 99.1       Limited Partnership Agreement of       Incorporated herein by
            Chesapeake Investments, an Oklahoma    reference to Exhibit E
            Limited Partnership                    to the Schedule 13D to the
                                                   Schedule 13D


 99.2       The Company's 1992 Incentive Stock     Incorporated herein by
            Option Plan as amended                 reference to Exhibit 10.1.1
                                                   to the Company's Registra-
                                                   tion Statementon Form S-4,
                                                   No. 33-93718, filed June
                                                   23, 1995

 99.3       The Company's 1992 Nonstatutory        Incorporated herein by
            Stock Option Plan, as amended          reference to Exhibit
                                                   10.1.2 to the Company's
                                                   Quarterly Report on Form
                                                   10-Q filed February 14,1997

 99.4       The Company's 1994 Stock Option Plan   Incorporated herein by
                                                   reference to Exhibit
                                                   10.1.3 to the Company's
                                                   Quarterly Report on Form
                                                   10-Q filed February 14,1997

 99.5       The Company's 1996 Stock Option Plan   Incorporated herein by
                                                   reference to Exhibit B
                                                   to the Company's definitive
                                                   proxy statement for its
                                                   1996 annual meeting of
                                                   shareholders filed
                                                   November 6, 1996

 99.6      The Company's 1999 Stock Option Plan    Incorporated herein by
                                                   reference to Exhibit 10.1.5
                                                   to the Company's quarterly
                                                   report on Form 10-Q for the
                                                   quarter ended June 30, 1999

 99.7      The Company's 2000 Employee Stock       Incorporated herein by
           Option Plan                             reference to Exhibit 10.1.6
                                                   to the Company's quarterly
                                                   report on Form 10-Q for the
                                                   quarter ended March 31,2000

 99.8      The Company's 2000 Executive Officer    Incorporated herein by
           Stock Option Plan                       reference to Exhibit 10.1.7
                                                   to the Company's quarterly
                                                   report on Form 10-Q for the
                                                   quarter ended March 31, 2000

 99.9      The Company's 2001 Stock Option Plan    Incorporated herein by
                                                   reference to Exhibit B
                                                   to the Company's definitive
                                                   proxy statement for its 2001
                                                   annual meeting of
                                                   shareholders filed
                                                   April 30, 2001

99.10     The Company's 2001 Executive Officer     Incorporated herein by
          Stock Option Plan                        reference to Exhibit 10.1.9
                                                   to the Company's quarterly
                                                   report on Form 10-Q for the
                                                   quarter ended June 30, 2001

99.11     The Company's 2001 Nonqualified Stock    Incorporated herein by
          Option Plan                              reference to Exhibit 10.1.10
                                                   to the Company's quarterly
                                                   report on Form 10-Q for the
                                                   quarter ended June 30, 2001

99.12     The Company's 2002 Stock Option Plan     Incorporated herein by
                                                   reference to Exhibit A to
                                                   the Company's definitive
                                                   proxy statement for its
                                                   2002 annual meeting of
                                                   shareholders filed
                                                   April 29, 2002

                                       15


CUSIP NO. 16517 10 7

99.13     The Company's 2002 Nonqualified Stock    Incorporated herein by
          Option Plan                              reference to Exhibit 10.1.11
                                                   to the Company's quarterly
                                                   report on Form 10-Q for the
                                                   quarter ended June 30, 2002

99.14     The Company's 2003 Stock                 Incorporated herein by
          Incentive Plan                           reference to Exhibit A
                                                   to the Company's definitive
                                                   proxy statement for its 2003
                                                   annual meeting of
                                                   shareholders filed
                                                   April 17, 2003

99.15     The Company's 401(k) Make-Up Plan       Incorporated herein by
                                                  reference to Exhibit 10.1.15
                                                  to the Company's annual report
                                                  on Form 10-K for the year
                                                  ended December 31, 2002

99.16     Common Stock Purchase Option No.        Incorporated herein by
          AKM-1 dated March 10, 1999, executed    reference to Exhibit 13 to
          by Aubrey K. McClendon in favor of      Amendment No. 2 to Schedule
          Frederick B. Whittemore.                13D filed by the Reporting
                                                  Persons on December 2, 1999

99.17     Common Stock Purchase Option No.        Incorporated herein by
          TLW-1 dated March 10, 1999, executed    reference to Exhibit 14
          by Tom L. Ward in favor of Frederick    to Amendment No. 2 to
          B. Whittemore.                          Schedule 13D filed by the
                                                  Reporting Persons on
                                                  December 2, 1999

99.18     Joint Filing Agreement                  Filed herewith electronically