California Code, Insurance Code - INS § 10089.19

(a) Participating insurers that want to withdraw from the authority may do so on 12 months' written notice to the authority.  Insurers that withdraw shall not be entitled to any refund, reimbursement, or reduction of any initial capital contribution obligation or earthquake loss assessments previously paid or accrued with respect to losses incurred prior to the withdrawal.  Insurers that withdraw shall offer residential earthquake insurance coverage pursuant to Chapter 8.5 (commencing with Section 10081) to those policyholders for whom they write the underlying residential property insurance upon the first renewal following the insurer's notice to the authority.  The authority shall nonrenew all policies of basic residential earthquake insurance issued to policyholders whose provider of residential earthquake insurance has withdrawn from the authority.  No participating insurer may withdraw unless every insurer affiliated with that insurer, as defined in subdivision (a) of Section 1215, or under common control with that insurer, defined in subdivision (c) of Section 1215, simultaneously withdraws from the authority.

(b) If a noticed withdrawal would result in participation by insurers whose cumulative residential property insurance market share is less than 65 percent of the total residential property insurance market in California, the commissioner shall make recommendations to the Legislature for the continuation or termination of the authority.