Cal. Code of Civil Procedure § 2032.630

By demanding and obtaining a report of a physical or mental examination under Section 2032.610 or 2032.620, or by taking the deposition of the examiner, other than under Article 3 (commencing with Section 2034.410) of Chapter 18, the party who submitted to, or produced another for, a physical or mental examination waives in the pending action, and in any other action involving the same controversy, any privilege, as well as any protection for work product under Chapter 4 (commencing with Section 2018.010), that the party or other examinee may have regarding reports and writings as well as the testimony of every other physician, psychologist, or licensed health care practitioner who has examined or may thereafter examine the party or other examinee in respect of the same physical or mental condition.