California Code, Revenue and Taxation Code - RTC § 756

(a) On or before July 31, the board shall transmit to each county auditor a roll showing the unitary and operating nonunitary assessments made by the board in the county and the nonoperating nonunitary assessments made by the board in each city and revenue district in the county;  provided, however, that the roll need not show the assessments made by the board in a revenue district which did not levy a tax or assessment during the preceding year.  The roll is at all times, during office hours, open to the inspection of any person representing any taxing agency or revenue district, or any district described in Section 2131.  If the roll does not show the assessments in a revenue district as herein provided and a notice of a proposed levy is furnished to the board in writing, on or before January 1 preceding the fiscal year for which the levy is to be made, the board shall furnish an estimate of the total assessed value of nonoperating nonunitary state-assessed property in the district and shall transmit thereafter to the county auditor a statement of roll change showing the nonoperating nonunitary assessments made by the board in the district.

(b) Notwithstanding subdivision (a), in making the roll referred to in subdivision (a), the value of property described in paragraph (1) of subdivision (a) of Section 100.1 and the nonunitary value of the property of regulated railway companies, property subject to subdivisions (i), (j), (k), and (l) of Section 100, and property subject to Section 100.9 shall be enrolled by revenue district.

(c) The amendments made to this section by the act  1 that added this subdivision apply for the 2007-08 fiscal year and for each fiscal year thereafter.