United States securities and exchange commission logo May 21, 2024 Christopher Senner Executive Vice President and Chief Financial Officer EXELIXIS, INC. 1851 Harbor Bay Parkway Alameda, CA 94502 Re: EXELIXIS, INC. Form 10-K for the Year Ended December 29, 2023 Filed February 6, 2024 File No. 000-30235 Dear Christopher Senner: We have completed our review of your filing. We remind you that the company and its management are responsible for the accuracy and adequacy of their disclosures, notwithstanding any review, comments, action or absence of action by the staff. Sincerely, Division of Corporation Finance Office of Life Sciences