Whenever an admitted insurer fails to take any step necessary to maintain continuance of its certificate of authority, or whenever the certificate of authority admitting an insurer is canceled or revoked, or whenever an admitted insurer as an entity ceases doing an insurance business in this state for any reason, such insurer shall apply to withdraw as an insurer and shall withdraw as such insurer from this state pursuant to this article. Every certificate of authority hereafter granted is so granted subject to this withdrawal requirement. Acceptance of every such certificate of authority is an agreement by the accepting insurer that it will conform to the provisions of this article.
Ca. Ins. Code § 1070.5