California Code, Government Code - GOV § 20283

(a) Any employer that fails to enroll an employee into membership when he or she becomes eligible, or within 90 days thereof, when the employer knows or can reasonably be expected to have known of that eligibility shall be required to pay all arrears costs for member contributions and administrative costs of five hundred dollars ($500) per member as a reimbursement to this system's current year budget.

(b) An employer shall not pass on to an employee any costs assessed pursuant to subdivision (a).