Section 117A. Two or more stock or two or more mutual fire companies authorized to transact business under the second clause of section forty-seven or under the eighth clause thereof may issue a single policy of insurance against loss or damage caused by any or all of the hazards specified in said second clause or in said eighth clause, as the case may be, on property or interests in the commonwealth on which each company shall be severally liable for a specified percentage of any loss or claim. Such policy shall be executed by the duly authorized officers of each company subject to the provisions of section thirty-three in the case of a domestic company.

No such policy shall be issued or delivered until a copy of the form thereof has been on file for thirty days with the commissioner, unless before the expiration of said thirty days he shall approve the form of the policy in writing; nor if the commissioner notifies the company in writing within thirty days that in his opinion the form of the policy does not comply with the laws of the commonwealth, specifying his reasons therefor, provided, that such action of the commissioner shall be subject to review by the supreme judicial court; nor unless it is headed by the corporate name of each company, nor unless it contains in substance the provisions numbered (1), (3), (4) and (5) in section one hundred and two A and a provision that any notice, sworn statement or proof of loss, which may be required by the provisions of said policy may be rendered, made or given to any one of such companies or to a duly authorized agent of any one of such companies, and that such notice, sworn statement or proof of loss so rendered, made or given shall be valid and binding as to all of such companies.

The provisions of sections seventy-six, eighty, eighty-one, eighty-three and ninety-eight applicable to policies issued by mutual fire companies, persons insured under such policies and dividends and assessments thereunder shall apply to each policy issued under this section by mutual companies, to persons insured thereunder and to dividends and assessments thereunder, except as hereinafter provided.

The person insured under such a policy issued as aforesaid by mutual companies shall be deemed to be a member of each such company while the policy is in force and entitled to one vote at the meetings of each company.

The notice, endorsement and statement required by said sections seventy-six, eighty and eighty-one, respectively, shall be in such form and in such place on the policy as the commissioner shall prescribe.

The dividend under said section eighty and the contingent mutual liability of the insured fixed by said sections eighty-one and eighty-three in respect to each such company shall be computed or based on such proportion of the total premium for the policy as the amount insured by such company bears to the full amount insured under the policy.

The notice to policyholders required by said section eighty shall be sent by each such company to the insured. The provisions of said section ninety-eight shall apply to the application, if any, of the insured to each such company and to their by-laws.

Nothing in this section shall be construed as affecting, except as provided herein, any provision of law relative to the rights, powers, duties and liabilities of mutual fire companies and persons insured thereby.