California Code, Government Code - GOV § 990.8

(b) Two or more local public entities having the same governing board, a mutual water company and a public agency, or a water corporation, a mutual water company, and one or more public agencies, as authorized under subdivision (b) of Section 6525, may be coinsured under a master policy and the total premium may be prorated among those entities.

(c) The pooling of self-insured claims or losses among entities as authorized in subdivision (a) of Section 990.4 shall not be considered insurance nor be subject to regulation under the Insurance Code.

(d) Any liability or loss under a joint powers agreement for the pooling of self-insured claims or losses authorized by this part and provided pursuant to this section may, notwithstanding Section 620 of the Insurance Code or any other provision of law, be reinsured to the same extent and the same manner as insurance provided by an insurer.

(e) If a joint powers agreement authorized by this part or authorized pursuant to Section 6516 provides for the pooling of self-insured claims or losses among entities, if any peril insured or covered under contract has existed, and the joint powers authority or other parties to the pool have been liable for any period, however short, the agreement may provide that the party insured or covered under contract is not entitled to the return of premiums, contributions, payments, or advances so far as that particular risk is concerned.

(f) For purposes of this section: