Cal. Code of Civil Procedure § 2025.530

(a) If there is no stenographic transcription of the deposition, the deposition officer shall send written notice to the deponent and to all parties attending the deposition that the audio or video recording made by, or at the direction of, any party, is available for review, unless the deponent and all these parties agree on the record to waive the hearing or viewing of the audio or video recording of the testimony. (b) For 30 days following a notice under subdivision (a), the deponent, either in person or by signed letter to the deposition officer, may change the substance of the answer to any question. (c) The deposition officer shall set forth in a writing to accompany the recording any changes made by the deponent, as well as either the deponent’s signature identifying the deposition as the deponent’s own, or a statement of the deponent’s failure to supply the signature, or to contact the officer within the period prescribed by subdivision (b). (d) When a deponent fails to contact the officer within the period prescribed by subdivision (b), or expressly refuses by a signature to identify the deposition as the deponent’s own, the deposition shall be given the same effect as though signed. (e) Notwithstanding subdivision (d), on a reasonable motion to suppress the deposition, accompanied by a meet and confer declaration under Section 2016.040, the court may determine that the reasons given for the refusal to sign require rejection of the deposition in whole or in part. (f) The court shall impose a monetary sanction under Chapter 7 (commencing with Section 2023.010) against any party, person, or attorney who unsuccessfully makes or opposes a motion to suppress a deposition under this section, unless it finds that the one subject to the sanction acted with substantial justification or that other circumstances make the imposition of the sanction unjust.