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                                                                    Exhibit 99.2

                                   DYAX CORP.

                   CERTIFICATION OF PERIODIC FINANCIAL REPORT
                       PURSUANT TO 18 U.S.C. SECTION 1350

     Each of the undersigned officers of Dyax Corp. (the "Company") certifies,
to his knowledge and solely for the purposes of 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the
Annual Report on Form 10-K of the Company for the year ended December 31, 2002
fully complies with the requirements of Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 and information contained in that Form 10-K fairly
presents, in all material respects, the financial condition and results of
operations of the Company.


Dated:   March 27, 2003                 /s/ Henry E. Blair
                                        ----------------------------------------
                                        Henry E. Blair
                                        Chief Executive Officer


Dated:   March 27, 2003                 /s/ Stephen S. Galliker
                                        ----------------------------------------
                                        Stephen S. Galliker
                                        Chief Financial Officer


A signed original of this written statement required by Section 906 has been
provided to the Company and will be retained by the Company and furnished to the
Securities and Exchange Commission or its staff upon request.