2005 California Revenue and Taxation Code Sections 12411-12414 Article 2. Initial Assessments

12411.  A duplicate copy of each tax return received by the
commissioner shall be promptly forwarded to the board.
12412.  Upon receipt of the duplicate copy of the return of an
insurer the board shall initially assess the tax in accordance with
the data as reported by the insurer on the return.
12413.  The board shall promptly transmit notice of its initial
assessment to the commissioner and the Controller, and if the initial
assessment differs from the amount computed by the insurer, notice
shall also be given to the insurer.
12414.  In making an initial assessment the board may offset an
overpayment for one calendar year against an underpayment for another
calendar year, against penalties, and against any interest on an
underpayment.