California Code, Labor Code - LAB § 1162

(a) An employer who petitions for a writ of review in a court of appeal or the California Supreme Court or otherwise appeals, petitions, or seeks to overturn or stay or modify any order of the board under this part involving make-whole, backpay, or other monetary award or economic benefit to employees or a labor organization shall, as a condition to seeking review, appeal, modification, or stay, post a bond, in the amount of the entire economic value of the order as determined by the board, to ensure that employees or the labor organization receive the benefits of the order if the employer does not prevail.

(b) The bond shall consist of an appeal bond issued by a licensed surety or a cash deposit with the board in the amount of the order, decision, or award. The employer shall provide written notification to all of the parties of the posting of the bond. The bond shall be on the condition that, if any judgment is entered against the employer, the employer shall pay the amount owed pursuant to the judgment, and if the appeal, petition, or action is withdrawn or dismissed without entry of judgment, the employer shall pay the amount owed pursuant to the order, decision, or award of the board unless the parties have executed a settlement agreement for payment of some other amount, in which case the employer shall pay the amount that the employer is obligated to pay under the terms of the settlement agreement. If the employer fails to pay the amount owed within 10 days of entry of the judgment, dismissal, or withdrawal of the appeal, or the execution of a settlement agreement, the bond is forfeited to the employee or employees or labor organization.