Cal. Insurance Code § 11529.5

Any such plan of mutualization may provide for the creation of a voting trust under a trust agreement for the holding and voting by three or more trustees of any portion or all of the shares of the insurer not acquired upon the adoption of such plan. The voting trustees shall be named in accordance with such plan or, if no provision is made therein for the naming of such trustees, then by the insurer. The voting trust agreement and voting trustees shall be subject to the approval of the commissioner. Any or all of the trustees under such voting trust agreement may be the same person or persons as any or all of the trustees referred to in Section 11529. Such voting trust agreement shall provide that in the event of acquisition by the insurer of any of the shares of stock held thereunder in accordance with the provisions of the plan, such shares so acquired together with the voting rights thereof shall be transferred by the trustees named under the provisions of this section to the trustees named under the provisions of Section 11529. Any voting trust agreement created pursuant to the provisions of this section may be made irrevocable for not longer than thirty (30) years and thereafter until the termination of the trust provided for in Section 11529. The trust created pursuant to the provisions of this section shall terminate in any event upon termination of the trust provided for in Section 11529. Upon the termination of the trust created pursuant to the provision of this section, any shares held in such trust shall revert to the persons entitled thereto by law.