Cal. RTC § 19565

(a) (1) If an organization is exempt from taxation under Section 23701 for any taxable year, the application filed by the organization with respect to which the Franchise Tax Board made its determination that the organization was entitled to exemption under Section 23701, together with any papers submitted in support of the application, any letter or other document issued by the Franchise Tax Board, with respect to the application, and any copy of the notification issued by the Internal Revenue Service approving the organization’s tax-exempt status pursuant to the Internal Revenue Code which is submitted by the organization to the Franchise Tax Board, shall be open to public inspection. After the application of any organization has been opened to public inspection under this subdivision, the Franchise Tax Board shall, on the request of any person with respect to the organization, furnish a statement indicating the section which it has been determined describes the organization.

(2) Any inspection under paragraph (1) may be made at times, and in the manner, as the Franchise Tax Board shall by regulation prescribe.

(b) Upon request of the organization submitting any supporting papers described in subdivision (a), the Franchise Tax Board shall withhold from public inspection any information contained therein which it determines relates to any trade secret, patent, process, style of work, or apparatus, of the organization, if it determines that public disclosure of the information would adversely affect the organization. The Franchise Tax Board shall withhold from public inspection any information contained in supporting papers described in subdivision (a) the public disclosure of which it determines would adversely affect the national defense.

(c) The Franchise Tax Board may impose a reasonable charge for supplying any information the disclosure of which is permitted under this section.