Cal. Pub. Util. Code § 741.2

(a) No nonpublic utility provider of telephone services, including, but not limited to, a hotel, motel, hospital, university, or similar place of temporary accommodation owning or operating message switching or billing equipment solely for the purpose of reselling services provided by a telephone corporation to its patients or guests is required to file or maintain tariff schedules.
(b) No such nonpublic utility provider of telephone services which provides service to hospital patients may charge more for any nontoll telephone call than the maximum rate of charge authorized by the commission for a nontoll call placed from a coin-activated telephone owned or operated by other than a telephone corporation plus twenty-five cents ($0.25).
(c) No such nonpublic utility provider of telephone services which provides service to hospital patients may charge more for any toll telephone call than the sum of all of the following:
1. (1) The applicable tariff rate or charge of the telephone corporation whose service is resold for that telephone call.
2. (2) The surcharge or surcharges, if any, applicable to that call if placed from a coin-activated telephone owned or operated by the telephone corporation within whose service area the nonpublic utility provider of telephone services is located, unless that surcharge is included in the tariff rate or charge for that call.
3. (3) Twenty-five cents ($0.25).
(d) No such nonpublic utility provider of telephone services may make any charge for any uncompleted telephone call unless notice pursuant to subdivision (e) is provided specifying the circumstances under which a charge will be made for an uncompleted call.
(e) Every nonpublic utility provider of telephone services shall display or post on or near the telephone equipment so as to be easily seen by telephone users a notice of all of the following:
1. (1) The charges applicable to all of the available telephone services. These charges shall be separately stated, and shall include, but not be limited to, the following information:
  1. (A) Individual customer telephone service activation deposits or fees, if any.
  2. (B) Charges for use of telephone services, irrespective of whether a call is completed.
2. (2) That these charges are consistent with this section, if applicable.
3. (3) The telephone number of the Consumer Affairs Division of the commission to which questions or complaints may be directed.
(f) Subdivision (e) does not require separate notices for multiple or extension telephones having the same telephone extension number.
(g) This section does not require any such nonpublic utility provider of telephone services to make any charge for the furnishing of any telephone service, and this section does not apply to any such provider that makes no charge for telephone services furnished. This section does not constitute any such provider a telephone corporation or otherwise subject it to regulation by the commission as a public utility.