California Code, Government Code - GOV § 15619

(a) Any information concerning the business affairs of any company that is gained during an examination of its books and accounts or in any other manner, and is not required by law to be reported to the State Board of Equalization.

(b) Any information, other than the assessment and the amount of taxes levied, obtained by the State Board of Equalization in accordance with law from any company other than one concerning which that information is required by law to be made public.

(c) Any particular item of information relating to the disposition of its earnings contained in the report of a quasi-public corporation that the corporation, by written communication specifying the items and presented at the time when it files its report, requests shall be treated as confidential.

Nothing in this section shall be construed as preventing examination of these records and reports by law enforcement agencies, grand juries, boards of supervisors, or their duly authorized agents, employees or representatives conducting an investigation of an assessor's office pursuant to Section 25303, and other duly authorized legislative or administrative bodies of the state pursuant to their authorization to examine these records.

Successors, receivers, trustees, executors, administrators, assignees, and guarantors, if directly interested, may be given information as to the items included in the measure and amounts of any unpaid tax or amounts of tax required to be collected, interest, and penalties.

The Governor may authorize examination of these reports by other state officers.  In that event the information obtained by these persons shall not be made public.  The Governor, however, may direct that any of the information referred to in this section shall be made public.

Any violation of this section is a misdemeanor and punishable by a fine not to exceed one thousand dollars ($1,000), or by imprisonment not to exceed six months, or both, at the discretion of the court.