2009 California Code of Civil Procedure - Section 2020.010-2020.030 :: Article 1. General Provisions

2020.010.  (a) Any of the following methods may be used to obtain
discovery within the state from a person who is not a party to the
action in which the discovery is sought:
   (1) An oral deposition under Chapter 9 (commencing with Section
2025.010).
   (2) A written deposition under Chapter 11 (commencing with Section
2028.010).
   (3) A deposition for production of business records and things
under Article 4 (commencing with Section 2020.410) or Article 5
(commencing with Section 2020.510).
   (b) Except as provided in subdivision (a) of Section 2025.280, the
process by which a nonparty is required to provide discovery is a
deposition subpoena.

2020.020.  A deposition subpoena may command any of the following:
   (a) Only the attendance and the testimony of the deponent, under
Article 3 (commencing with Section 2020.310).
   (b) Only the production of business records for copying, under
Article 4 (commencing with Section 2020.410).
   (c) The attendance and the testimony of the deponent, as well as
the production of business records, other documents, and tangible
things, under Article 5 (commencing with Section 2020.510).

2020.030.  Except as modified in this chapter, the provisions of
Chapter 2 (commencing with Section 1985) of Title 3 of Part 4 of this
code, and of Article 4 (commencing with Section 1560) of Chapter 2
of Division 11 of the Evidence Code, apply to a deposition subpoena.