Cal. Rev. & Tax. Code § 6072

A permit shall be held only by persons actively engaging in or conducting a business as a seller of tangible personal property. Any person not so engaged shall forthwith surrender his or her permit to the board for cancellation. The board may revoke the permit of a person found to be not actively engaged in or conducting a business as a seller of tangible personal property.

Any person who knowingly issues a resale certificate while the person is not actively engaged in business as a seller, for personal gain or to evade the payment of taxes, shall be liable for the taxes that would otherwise have been due on the transaction, plus a penalty of 10 percent or five hundred dollars ($500), whichever is greater, in addition to all other penalties imposed by this part, and interest at the modified adjusted rate per month, or fraction thereof, established pursuant to Section 6591.5, from the last day of the month following the quarterly period for which the amount or any portion thereof should have been returned until the date of payment.