Cal. Rev. & Tax. Code § 8106

In lieu of the collection and refund of the tax on tax-paid motor vehicle fuel exported, removed, sold, or used by a supplier in a manner that would entitle the supplier to claim a refund under Section 8101, credit may be given the supplier upon the supplier’s tax return, and the determination of the amount of tax shall be determined in accordance with any rules and regulations the board may prescribe.