Cal. Code of Civil Procedure § 2031.010

(a) Any party may obtain discovery within the scope delimited by Chapter 2 (commencing with Section 2017.010), and subject to the restrictions set forth in Chapter 5 (commencing with Section 2019.010), by inspecting, copying, testing, or sampling documents, tangible things, land or other property, and electronically stored information in the possession, custody, or control of any other party to the action. (b) A party may demand that any other party produce and permit the party making the demand, or someone acting on the demanding party’s behalf, to inspect and to copy a document that is in the possession, custody, or control of the party on whom the demand is made. (c) A party may demand that any other party produce and permit the party making the demand, or someone acting on the demanding party’s behalf, to inspect and to photograph, test, or sample any tangible things that are in the possession, custody, or control of the party on whom the demand is made. (d) A party may demand that any other party allow the party making the demand, or someone acting on the demanding party’s behalf, to enter on any land or other property that is in the possession, custody, or control of the party on whom the demand is made, and to inspect and to measure, survey, photograph, test, or sample the land or other property, or any designated object or operation on it. (e) A party may demand that any other party produce and permit the party making the demand, or someone acting on the demanding party’s behalf, to inspect, copy, test, or sample electronically stored information in the possession, custody, or control of the party on whom demand is made.