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                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
 
                                  FORM 10-Q/A
 
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<C>           <S>
 (MARK ONE)
    [X]       QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
              OF THE SECURITIES EXCHANGE ACT OF 1934
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                  FOR THE QUARTERLY PERIOD ENDED JUNE 30, 1998
 
                                       OR
 
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<C>           <S>
    [ ]       TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
              OF THE SECURITIES EXCHANGE ACT OF 1934
</TABLE>
 
                          COMMISSION FILE NO. 1-10067
 
                            DEVON ENERGY CORPORATION
             (Exact Name of Registrant as Specified in its Charter)
 
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<CAPTION>
                  OKLAHOMA                                      73-1474008
<S>                                            <C>
       (State or Other Jurisdiction of                       (I.R.S. Employer
       Incorporation or Organization)                     Identification Number)
         20 N. BROADWAY, SUITE 1500
           OKLAHOMA CITY, OKLAHOMA                                 73102
  (Address of Principal Executive Offices)                      (Zip Code)
</TABLE>
 
       Registrant's telephone number, including area code: (405) 235-3611
 
                                 NOT APPLICABLE
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Former name, former address and former fiscal year, if changed from last report.
 
     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes [X]  No [ ].
 
     The number of shares outstanding of Registrant's common stock, par value
$.10, as of July 31, 1998, was 32,319,894.
 
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PART I. FINANCIAL INFORMATION
 
ITEM 1. CONSOLIDATED FINANCIAL STATEMENTS: No Changes.
 
ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
OF OPERATIONS is hereby amended to add the following disclosure at the end of
such item:
 
YEAR 2000 STATUS
 
     Devon's company-wide Year 2000 Project ("the Project") is proceeding on
schedule. The Project is addressing the Year 2000 issue caused by computer
programs being written utilizing two digits rather than four to define an
applicable year. As a result, Devon's computer equipment, software (all of which
is externally developed), and devices with embedded technology that are time
sensitive may misinterpret the actual date beginning on January 1, 2000. This
could result in a system failure or miscalculations causing disruptions of
operations, including, but not limited to, a temporary inability to process
transactions.
 
     Devon has undertaken various initiatives intended to ensure that its
computer equipment and software will function properly with respect to dates in
the Year 2000 and thereafter. In planning and developing the Project, Devon has
considered both its information technology ("IT") and its non-IT systems. The
term "computer equipment and software" includes systems that are commonly
thought of as IT systems, including accounting, data processing, telephone
systems, scanning equipment, and other miscellaneous systems. Those items not to
be considered as IT technology include alarm systems, fax machines, monitors for
field operations, or other miscellaneous systems. Both IT and non-IT systems may
contain embedded technology, which complicates Devon's Year 2000 identification,
assessment, remediation, and testing efforts. Based upon its identification and
assessment efforts to date, Devon is in the process of replacing the computer
equipment and software it currently uses to become Year 2000 complaint. In
addition, in the ordinary course of replacing computer equipment and software,
Devon plans to obtain replacements that are in compliance with Year 2000.
 
     Devon has also mailed letters to its significant vendors and service
providers and has verbally communicated with many strategic customers to
determine the extent to which interfaces with such entities are vulnerable to
Year 2000 issues and whether the products and services purchased from or by such
entities are Year 2000 compliant. Devon has received a favorable response from
such third parties and it is anticipated that their significant Year 2000 issues
will be addressed on a timely basis.
 
     With regard to IT, non-IT systems and communications with third parties,
Devon anticipates that the Project will be completed by June 30, 1999.
 
     As noted above, Devon is in the process of replacing certain computer
equipment and software because of the Year 2000 issue. Devon estimates that the
total cost of such replacements will approximate $0.3 million. Substantially all
of the personnel being used on the Project are existing Devon employees.
Therefore, the labor costs of its Year 2000 identification, assessment,
remediation and testing efforts, as well as currently anticipated labor costs to
be incurred by Devon with respect to Year 2000 issues of third parties, are
expected to be less than $0.1 million.
 
     Devon has not yet begun a comprehensive analysis of the operational
problems and costs that would be reasonably likely to result from the failure by
Devon and significant third parties to complete efforts necessary to achieve
Year 2000 compliance on a timely basis. A contingency plan has not been
developed for dealing with the most reasonably likely worst case scenario, and
such scenario has not yet been clearly identified. Devon plans to complete such
analysis and contingency planning by December 31, 1999.
 
     Devon presently does not expect to incur significant operational problems
due to the Year 2000 issue. However, if all Year 2000 issues are not properly
and timely identified, assessed, remediated and tested, there can be no
assurance that the Year 2000 issue will not materially impact Devon's results of
operations or adversely affect its relationships with customers, vendors, or
others. Additionally, there can be no assurance that the Year 2000 issues of
other entities will not have a material impact on Devon's systems or results of
operations.
 
PART II. OTHER INFORMATION: No Changes.
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                                   SIGNATURES
 
     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.
 
                                            DEVON ENERGY CORPORATION
 
                                                   /s/ DANNY J. HEATLY
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                                                      Danny J. Heatly
                                                         Controller
 
Date: October 14, 1998