Cal. Pub. Resources Code § 6835
Each bid (which shall be in the form of a lease prepared in accordance with this chapter) for an oil and gas lease shall be accompanied by a certified or cashier's check of a responsible bank in California payable to the State of California in an amount to be fixed by the commission, which sum shall be deposited as evidence of good faith and except in the case of the successful bidder shall be returned to the bidder. Upon the execution of the lease the amount shall be applied upon the annual rental for the first year and the balance, if any, shall be returned to the lessee. If the successful bidder fails or refuses to execute the lease within 15 days after the award thereof, the amount of the check shall be forfeited to the State.
Ca. Pub. Res. Code § 6835