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                                                                    Exhibit 31.2

                      CHIEF FINANCIAL OFFICER CERTIFICATION

I, Joseph S. De Vita, Chief Financial Officer of SeaBright Insurance Holdings,
Inc., certify that:

1. I have reviewed this quarterly report on Form 10-Q of SeaBright Insurance
Holdings, Inc.;

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) [Reserved]

   c) 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

   d) 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 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:

   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: May 11, 2005

                                 /s/ Joseph S. De Vita
                                 ----------------------------------------------
                                 Joseph S. De Vita
                                 Senior Vice President, Chief Financial Officer
                                 and Assistant Secretary