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Exhibit 32.1

CERTIFICATION

        Pursuant to the requirement set forth in Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. §1350), James M. Gower, Chief Executive Officer of Rigel Pharmaceuticals, Inc. (the "Company"), and Ryan D. Maynard, Executive Vice President and Chief Financial Officer of the Company, each hereby certifies that, to the best of his knowledge:

        In Witness Whereof, the undersigned have set their hands hereto as of March 5, 2013.

/s/ JAMES M. GOWER

James M. Gower
Chief Executive Officer
  /s/ RYAN D. MAYNARD

Ryan D. Maynard
Executive Vice President and Chief Financial Officer

        This certification accompanies the Form 10-K to which it relates, is not deemed filed with the Securities and Exchange Commission and is not to be incorporated by reference into any filing of Rigel Pharmaceuticals, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-K), irrespective of any general incorporation language contained in such filing.




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CERTIFICATION