California Code, Code of Civil Procedure - CCP § 2020.510

(a) A deposition subpoena that commands the attendance and the testimony of the deponent, as well as the production of business records, documents, electronically stored information, and tangible things, shall:

(b) A deposition subpoena under subdivision (a) need not be accompanied by an affidavit or declaration showing good cause for the production of the documents and things designated.

(c) If, as described in Section 1985.3, the person to whom the deposition subpoena is directed is a witness, and the business records described in the deposition subpoena are personal records pertaining to a consumer, the service of the deposition subpoena shall be accompanied either by a copy of the proof of service of the notice to the consumer described in subdivision (e) of Section 1985.3, or by the consumer's written authorization to release personal records described in paragraph (2) of subdivision (c) of Section 1985.3.

(d) If, as described in Section 1985.6, the person to whom the deposition subpoena is directed is a witness and the business records described in the deposition subpoena are employment records pertaining to an employee, the service of the deposition subpoena shall be accompanied either by a copy of the proof of service of the notice to the employee described in subdivision (e) of Section 1985.6, or by the employee's written authorization to release personal records described in paragraph (2) of subdivision (c) of Section 1985.6.