California Code, Insurance Code - INS § 11661.6

(a) An insurer shall not insure an employer against his or her obligation to reimburse the insurer for the amount of increase in indemnity payment as provided for by subdivision (e) of Section 4650 of the Labor Code.  Every contract insuring against liability for compensation and every compensation policy shall provide that the insured employer is obligated to reimburse the insurer for the amount of increase in indemnity payment required by Section 4650 of the Labor Code, if the late indemnity payment which gives rise to the increase in the amount of payment is due less than seven days after the insurer receives the completed claim form from the employer.

(b) An insurer shall not report the amount of any increase in indemnity required by Section 4650 of the Labor Code as incurred indemnity to the Insurance Commissioner's designated statistical agent.