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                                                                    Exhibit 31.2

                                  CERTIFICATION

I, Scott Keys, Executive Vice President and Chief Financial Officer of IndyMac
Bancorp, Inc. ("IndyMac Bancorp"), certify that:

1.    I have reviewed this quarterly report on Form 10-Q of IndyMac Bancorp;

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 (the registrant's fourth fiscal
         quarter in the case of an annual report) 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 (or persons performing the equivalent functions):

                  (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:   August 1, 2003

                                                        /s/ SCOTT KEYS
                                                  ---------------------------
                                                           Scott Keys
                                                    Executive Vice President
                                                  and Chief Financial Officer