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                                                                    EXHIBIT 31.1

I, James C. Day, certify that:

         1.       I have reviewed this quarterly report on Form 10-Q of Noble
                  Corporation;

         2.       Based on my knowledge, this report does not contain any untrue
                  statement of a material fact or omit to state a material fact
                  necessary to make the statements made, in light of the
                  circumstances under which such statements were made, not
                  misleading with respect to the period covered by this report;

         3.       Based on my knowledge, the financial statements, and other
                  financial information included in this report, fairly present
                  in all material respects the financial condition, results of
                  operations and cash flows of the registrant as of, and for,
                  the periods presented in this report;

         4.       The registrant's other certifying officer and I are
                  responsible for establishing and maintaining disclosure
                  controls and procedures (as defined in Exchange Act Rules
                  13a-15(e) and 15d-15(e)) for the registrant and have:

                           a) Designed such disclosure controls and procedures,
                           or caused such disclosure controls and procedures to
                           be designed under our supervision, to ensure that
                           material information relating to the registrant,
                           including its consolidated subsidiaries, is made
                           known to us by others within those entities,
                           particularly during the period in which this report
                           is being prepared;

                           b) Evaluated the effectiveness of the registrant's
                           disclosure controls and procedures and presented in
                           this report our conclusions about the effectiveness
                           of the disclosure controls and procedures, as of the
                           end of the period covered by this report based on
                           such evaluation; and

                           c) Disclosed in this report any change in the
                           registrant's internal control over financial
                           reporting that occurred during the registrant's most
                           recent fiscal quarter that has materially affected,
                           or is reasonably likely to materially affect, the
                           registrant's internal control over financial
                           reporting; and

         5.       The registrant's other certifying officer and I have
                  disclosed, based on our most recent evaluation of internal
                  control over financial reporting, to the registrant's auditors
                  and the audit committee of the registrant's board of
                  directors:

                           a) All significant deficiencies and material
                           weaknesses in the design or operation of internal
                           control over financial reporting which are reasonably
                           likely to adversely affect the registrant's ability
                           to record, process, summarize and report financial
                           information; and

                           b) Any fraud, whether or not material, that involves
                           management or other employees who have a significant
                           role in the registrant's internal control over
                           financial reporting.

Date: November 12, 2003

/s/ JAMES C. DAY
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James C. Day
Chairman and Chief Executive Officer of Noble Corporation