Cal. Code of Civil Procedure - CCP § 2020.310. Section 2020.310.
The following rules apply to a deposition subpoena that commands only the attendance and the testimony of the deponent:
(a)
The subpoena shall specify the time when and the place where the deponent is commanded to attend the deposition.
(b)
The subpoena shall set forth a summary of all of the following:
(1)
The nature of a deposition.
(2)
The rights and duties of the deponent.
(3)
The penalties for disobedience of a deposition subpoena, as described in Section 2020.240.
(c)
If the deposition will be recorded using audio or video technology by, or at the direction of, the noticing party under Section 2025.340, the subpoena shall state that it will be recorded in that manner.
(d)
If the deposition testimony will be conducted using instant visual display, the subpoena shall state that it will be conducted in that manner.
(e)
If the deponent is an organization, the subpoena shall describe with reasonable particularity the matters on which examination is requested. The subpoena shall also advise the organization of its duty to
make the designation of employees or agents who will attend the deposition, as described in Section 2025.230.