California Code, Penal Code - PEN § 1546.5

(a) A California corporation or a corporation whose principal executive offices are located in California that provides electronic communications services shall not, in California, provide records, information, facilities, or assistance in accordance with the terms of a warrant, court order, subpoena, wiretap order, pen register trap and trace order, or other legal process issued by, or pursuant to, the procedures of another state or a political subdivision thereof that relates to an investigation into or enforcement of a prohibited violation, as defined in Section 629.51.

(b) The Attorney General may commence a civil action to compel any California corporation or a corporation whose principal executive offices are located in California that provides electronic communications services to comply with the provisions of this section.

(c) A California corporation or a corporation whose principal executive offices are located in California, and its officers, employees, and agents, are not subject to any cause of action for providing records, information, facilities, or assistance in accordance with the terms of a warrant, court order, subpoena, wiretap order, pen register trap and trace order, or other legal process issued by, or pursuant to, the procedures of another state or a political subdivision thereof, except where the corporation knew or should have known that the warrant, court order, subpoena, wiretap order, pen register trap and trace order, or other legal process relates to an investigation into or enforcement of a prohibited violation, as defined in Section 629.51.