Cal. Code of Civil Procedure § 2033.080

(a) When requests for admission have been made, the responding party may promptly move for a protective order. This motion shall be accompanied by a meet and confer declaration under Section 2016.040. (b) The court, for good cause shown, may make any order that justice requires to protect any party from unwarranted annoyance, embarrassment, oppression, or undue burden and expense. This protective order may include, but is not limited to, one or more of the following directions: (1) That the set of admission requests, or particular requests in the set, need not be answered at all. (2) That, contrary to the representations made in a declaration submitted under Section 2033.050, the number of admission requests is unwarranted. (3) That the time specified in Section 2033.250 to respond to the set of admission requests, or to particular requests in the set, be extended. (4) That a trade secret or other confidential research, development, or commercial information not be admitted or be admitted only in a certain way. (5) That some or all of the answers to requests for admission be sealed and thereafter opened only on order of the court. (c) If the motion for a protective order is denied in whole or in part, the court may order that the responding party provide or permit the discovery against which protection was sought on terms and conditions that are just. (d) 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 for a protective order 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.