California Code, Labor Code - LAB § 3862

(a) Except as provided in subdivision (b), an employer entitled to and who has been allowed and has perfected a lien upon the judgment or award in favor of an employee against any third party for damages occasioned to the same employer by payment of compensation, expenses of medical treatment, and any other charges under this act, may enforce payment of the lien against the third party, or, in case the damages recovered by the employee have been paid to the employee, against the employee to the extent of the lien, in the manner provided for enforcement of money judgments generally.

(b) Pursuant to subdivision (b) of Section 3852, the employer's claim for reimbursement shall be limited to the portion of the settlement allocated to the employer.  The employer shall have no right to assert any credit or offset against future workers' compensation benefits.