California Code, Business and Professions Code - BPC § 2177

(c)(1) An applicant shall have obtained a passing score on all parts of Step 3 of the United States Medical Licensing Examination within not more than four attempts in order to be eligible for a physician's and surgeon's certificate.

(2) Notwithstanding paragraph (1), an applicant who obtains a passing score on all parts of Step 3 of the United States Medical Licensing Examination in more than four attempts and who meets the requirements of Section 2135 or2135.5 shall be eligible to be considered for issuance of a physician's and surgeon's certificate.