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                                                                    Exhibit 31.3

                           CERTIFICATION OF TREASURER
            Pursuant to Section 302 of the Sarbanes Oxley Act of 2002

I, Robert F. Aufenanger, certify that:

1. I have reviewed this annual report on Form 10-K of Excelsior Venture Partners
III, LLC;

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, changes in net assets, and cash
flows of the registrant as of, and for, the periods presented in this report;

4. The registrant's other certifying officers 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 officers 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: January 29, 2004


/s/ Robert F. Aufenanger
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Robert F. Aufenanger, Treasurer