Cal. Rev. & Tax. Code § 38705

Except as provided in Sections 38402 and 38706, it is unlawful for the board or any person having an administrative duty under this part to make known in any manner whatever the business affairs, operations, or any other information pertaining to any timber owner or any other person required to report to the board or pay a tax pursuant to this part, or the amount or source of income, profits, losses, expenditures, or any particular thereof, set forth or disclosed in any return, or to permit any return or copy thereof or any book containing any abstract or particulars thereof to be seen or examined by any person. However, the Governor may, by general or special order, authorize examination by other state officers, by tax officers of another state, by the federal government, if a reciprocal arrangement exists, or by any other person of the records maintained by the board under this part. The information so obtained pursuant to the order of the Governor shall not be made public except to the extent and in the manner that the order may authorize that it be made public.