California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 6478
# (a)
If a failure to make a prepayment as described in Section 6477 is due to negligence or intentional disregard of this part or authorized rules and regulations, the penalty shall be 10 percent instead of 6 percent.
# (b)
If any part of a deficiency in prepayment is due to negligence or intentional disregard of this part or authorized rules and regulations, a penalty of 10 percent of the deficiency shall be paid.
# (c)
The provisions of this section shall not apply to amounts subject to the provisions of Sections 6484, 6485, 6511, 6514, and 6591.
# (d)
The 10 percent negligence penalty shall become due and payable and shall be ascertained and determined in the same manner as the deficiency determination under Article 2 (commencing with Section 6481) of this chapter. The provisions of Article 5 (commencing with Section 6561) of this chapter shall be applicable with respect to the finality of the determination and the right to petition for redetermination.
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