EXEL · Exelixis, Inc.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 11, 2025.

Represents the weighted average sales price. The shares of Exelixis, Inc. common Stock ("Common Stock") were sold in multiple transactions at prices ranging from $49.73 to $50.61. Reporting Person undertakes to provide Exelixis, Inc., any security holder of Exelixis, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote 2 to this Form 4.

Includes 16,079 shares of Common Stock that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 19, 2025.

Includes 8,367 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 8,367 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 17,455 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 8,367 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Option granted to David Johnson ("Mr. Johnson") pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. The option is exercisable immediately, subject to repurchase provisions, and will vest as to 100% of the shares subject to the option on the first anniversary of the date of grant, subject to Mr. Johnson's continuous service through such date.

Mr. Johnson is deemed to hold the securities reported herein for the benefit of Caligan Partners Master Fund LP (the "Caligan Master Fund") and managed accounts to which Caligan Partners LP ("Caligan") serves as investment manager (the "Caligan Accounts", together with the Caligan Master Fund, the "Caligan Master Fund and Accounts"), and may, after vesting, if applicable, transfer the securities directly to the Caligan Master Fund and Accounts.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 16,079 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 8,367 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 8,367 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 17,455 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 16,079 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Represents restricted stock units ("RSUs") granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. Each RSU is the economic equivalent of one share of Exelixis, Inc. common stock ("Common Stock"). The RSUs will vest as to 100% of the shares subject to the RSU award on May 27, 2027, subject to the Reporting Person's continuous service through that date.

Includes 8,367 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs.

Includes 405,966 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"), and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Represents the weighted average sales price. The shares of Exelixis, Inc. common stock ("Common Stock") were sold in multiple transactions at prices ranging from $49.80 to $49.89. Reporting Person undertakes to provide Exelixis, Inc., any security holder of Exelixis, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote 1 to this Form 4.

Includes 356,992 shares of Common Stock that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"), and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 19, 2025.

Represents the weighted average sales price. The shares of Common Stock were sold in multiple transactions at prices ranging from $49.84 to $50.51. Reporting Person undertakes to provide Exelixis, Inc., any security holder of Exelixis, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote 4 to this Form 4.

Includes 106,039 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs, the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs") and 167 shares of Common Stock acquired on April 30, 2026, pursuant to the Exelixis, Inc. 2000 Employee Stock Purchase Plan. Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Represents the weighted average sales price. The shares of Common Stock were sold in multiple transactions at prices ranging from $50.00 to $50.07. Reporting Person undertakes to provide Exelixis, Inc., any security holder of Exelixis, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote 3 to this Form 4.

Includes 403,915 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

On May 18, 2026, the Reporting Person gifted 124,047 shares of Common Stock to Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Living Trust dated July 21, 1994, as amended.

Shares of Common Stock held by Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Living Trust dated July 21, 1994, as amended.

On May 18, 2026, the Reporting Person gifted 124,047 shares of Common Stock to Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Living Trust dated July 21, 1994, as amended.

Includes 1,362,008 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Shares withheld by Exelixis, Inc. to satisfy taxes payable in connection with the vesting of restricted stock units ("RSUs") awarded on March 4, 2022, April 3, 2023, February 23, 2024, and February 26, 2025.

Includes 405,966 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs, the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs") and 646 shares of Common Stock acquired on April 30, 2026, pursuant to the Exelixis, Inc. 2000 Employee Stock Purchase Plan. Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Shares withheld by Exelixis, Inc. to satisfy taxes payable in connection with the vesting of restricted stock units ("RSUs") awarded on March 4, 2022, February 29, 2024, and February 26, 2025.

Includes 106,039 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs, the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs") and 167 shares of Common Stock acquired on April 30, 2026, pursuant to the Exelixis, Inc. 2000 Employee Stock Purchase Plan. Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Shares withheld by Exelixis, Inc. to satisfy taxes payable in connection with the vesting of restricted stock units ("RSUs") awarded on March 4, 2022, April 3, 2023, February 23, 2024, and February 26, 2025.

Includes 1,362,008 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Shares withheld by Exelixis, Inc. to satisfy taxes payable in connection with the vesting of restricted stock units ("RSUs") awarded on March 4, 2022, April 3, 2023, February 23, 2024, and February 26, 2025.

Includes 356,992 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs, the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs") and 646 shares of Common Stock acquired on April 30, 2026, pursuant to the Exelixis, Inc. 2000 Employee Stock Purchase Plan. Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Shares withheld by Exelixis, Inc. to satisfy taxes payable in connection with the vesting of restricted stock units ("RSUs") awarded on March 4, 2022, April 3, 2023, February 23, 2024, and February 26, 2025.

Includes 403,915 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

The option, representing the right to purchase a total of 20,634 shares of Common Stock, became fully exercisable on May 23, 2019.

Represents the weighted average sales price. The shares of Exelixis, Inc. common stock ("Common Stock") were sold in multiple transactions at prices ranging from $45.65 to $45.85. Reporting Person undertakes to provide Exelixis, Inc., any security holder of Exelixis, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote 1 to this Form 4.

Includes 9,812 shares of Common Stock that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

Includes 17,524 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

The option, representing the right to purchase a total of 30,848 shares of Common Stock, became fully exercisable on January 5, 2024.

Includes 9,812 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

Includes 9,812 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

Includes 17,524 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

On May 6, 2026, the Reporting Person gifted 109,676 shares of Exelixis, Inc. common stock ("Common Stock") to the Bombora Rise Foundation.

Shares of Common Stock held by Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Living Trust dated July 21, 1994, as amended.

Represents shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon the vesting of restricted stock units ("RSUs"). The RSUs were granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. The RSUs will vest as to 1/4th of the original number of shares subject to the RSU award on May 15, 2027 and thereafter as to 1/4th of the original number of shares subject to the RSU award on each May 15th until fully vested.

Includes 422,367 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Represents shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon the vesting of restricted stock units ("RSUs"). The RSUs were granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. The RSUs will vest as to 1/4th of the original number of shares subject to the RSU award on May 15, 2027 and thereafter as to 1/4th of the original number of shares subject to the RSU award on each May 15th until fully vested.

Includes 466,061 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Represents shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon the vesting of restricted stock units ("RSUs"). The RSUs were granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. The RSUs will vest as to 1/4th of the original number of shares subject to the RSU award on May 15, 2027 and thereafter as to 1/4th of the original number of shares subject to the RSU award on each May 15th until fully vested.

Includes 119,075 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Represents shares of Common Stock that will be issued to the Reporting Person upon the vesting of restricted stock units ("RSUs"). The RSUs were granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. The RSUs will vest as to 1/4th of the original number of shares subject to the RSU award on May 15, 2027 and thereafter as to 1/4th of the original number of shares subject to the RSU award on each May 15th until fully vested.

Includes 1,614,552 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Represents shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon the vesting of restricted stock units ("RSUs"). The RSUs were granted to the Reporting Person on the Transaction Date pursuant to the Exelixis, Inc. 2017 Equity Incentive Plan. The RSUs will vest as to 1/4th of the original number of shares subject to the RSU award on May 15, 2027 and thereafter as to 1/4th of the original number of shares subject to the RSU award on each May 15th until fully vested.

Includes 479,708 shares of Common Stock that will be issued to the Reporting Person upon vesting of RSUs and the performance-based restricted stock unit award granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

On February 24, 2026, the Reporting Person gifted 100,278 shares of Exelixis, Inc. common stock ("Common Stock") to the Bombora Rise Foundation.

Shares held by Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Living Trust dated July 21, 1994, as amended.

Includes 414,043 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs") and PSUs granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Includes 414,043 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs") and PSUs granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

The option, representing the right to purchase a total of 44,087 shares of Common Stock, became fully exercisable on June 1, 2023.

The option, representing the right to purchase a total of 20,030 shares of Common Stock, became fully exercisable on May 31, 2024.

Includes 9,812 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

On February 18, 2026, the Reporting Person gifted 125,094 shares of Common Stock to Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Trust dated July 21, 1994, as amended.

Shares held by Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Living Trust dated July 21, 1994, as amended.

The sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 19, 2025.

Represents the weighted average sales price. The shares were sold in multiple transactions at prices ranging from $43.32 to $44.49. Reporting Person undertakes to provide Exelixis, Inc., any security holder of Exelixis, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnote 4 to this Form 4.

Includes 95,956 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs") and PSUs granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

The option, representing the right to purchase a total of 20,634 shares of Common Stock, became fully exercisable on May 23, 2019.

Includes 9,812 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

On February 18, 2026, the Reporting Person gifted 125,094 shares of Common Stock to Michael M. Morrissey and Meghan D. Morrissey, Trustees of the Morrissey Family Trust dated July 21, 1994, as amended.

Includes 1,454,115 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs") and PSUs granted to the Reporting Person on March 31, 2025 ("One-Time Award PSUs"). Each RSU is the economic equivalent of one share of Common Stock and each One-Time Award PSU represents a contingent right to receive one share of Common Stock.

Includes 9,812 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

Includes 9,812 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.

Includes 9,812 shares of Exelixis, Inc. common stock ("Common Stock") that will be issued to the Reporting Person upon vesting of restricted stock units ("RSUs"). Each RSU is the economic equivalent of one share of Common Stock.