California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 38607
Official textleginfo.legislature.ca.gov
# (a)
If the board determines that any overpayment has been made intentionally or by reason of carelessness, it shall not allow any interest thereon.
# (b)
If any person who has filed a claim for refund requests the board to defer action on the claim, the board, as a condition to deferring action, may require the claimant to waive interest for the period during which the person requests the board to defer action on the claim.
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