X0206 3 2023-05-01 0 0001515673 Ultragenyx Pharmaceutical Inc. RARE 0001653052 Crombez Eric C/O ULTRAGENYX PHARMACEUTICAL INC. 60 LEVERONI COURT NOVATO CA 94949 0 1 0 0 EVP and Chief Medical Officer Common Stock 25854 D Stock Option (Right to Buy) 48.11 2027-11-17 Common Stock 7500 D Stock Option (Right to Buy) 67.55 2029-03-01 Common Stock 8000 D Stock Option (Right to Buy) 56.08 2030-03-01 Common Stock 13000 D Stock Option (Right to Buy) 142.47 2031-03-01 Common Stock 4310 D Stock Option (Right to Buy) 67.37 2032-03-01 Common Stock 6335 D Stock Option (Right to Buy) 45.65 2033-03-01 Common Stock 9845 D Includes 12,601 Restricted Stock Units ("RSUs") awarded under the Company's 2014 Incentive Plan. The RSUs vest with respect to 1/4th of the underlying shares on each anniversary of the grant date, such that the RSUs are fully vested on the fourth anniversary of the grant date. Of the 12,601 RSUs, 1,115 RSUs were granted on March 1, 2020, 720 RSUs were granted on March 1, 2021, 1,000 RSUs were granted on April 16, 2021, 2,381 RSUs were granted on March 1, 2022 and 7,385 RSUs were granted on March 1, 2023. 1/4th of the shares initially subject to the option vested on November 17, 2018; thereafter, 1/48th of the shares initially subject to the option vested monthly. 1/4th of the shares initially subject to the option vested on March 1, 2020; thereafter, 1/48th of the shares initially subject to the option vested monthly. 1/4th of the shares initially subject to the option vested on March 1, 2021 thereafter, 1/48th of the shares initially subject to the option shall vest monthly. 1/4th of the shares initially subject to the option vested on March 1, 2022 thereafter, 1/48th of the shares initially subject to the option shall vest monthly. 1/4th of the shares initially subject to the option vested on March 1, 2023 thereafter, 1/48th of the shares initially subject to the option shall vest monthly. 1/4th of the shares initially subject to the option will vest on March 1, 2024 thereafter, 1/48th of the shares initially subject to the option shall vest monthly. /s/ Karah Parschauer, attorney-in-fact 2023-05-02