California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 55042
# (a)
Any person who fails to pay any fee, except fees determined by the board under Article 2 (commencing with Section 55061), within the time required shall pay a penalty of 10 percent of the amount of the fee, together with interest on that fee at the modified adjusted rate per month, or fraction thereof, established pursuant to Section 6591.5, from the date on which the fee became due and payable until the date of payment.
# (b)
Any person who fails to file a return within the time prescribed for filing the return shall pay a penalty of 10 percent of the amount of the fee with respect to the period for which the return is required.
# (c)
The penalties imposed by this section shall be limited to a maximum of 10 percent of the fee for which the return is required for any one return.
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