Section 152A. Any mutual fire company admitted before or after this section takes effect to transact business in this commonwealth may issue non-assessable policies in compliance with the requirements of section eighty-five A and any such mutual company, or any company specified in the first paragraph of section ninety, may issue non-assessable policies in compliance with the requirements of section ninety-three F, except that the deposit required in either case may be made in the home state of such admitted company in cash or securities legal for investments by such companies in such home state. Any deposit required for the purposes specified in either of said sections shall be inclusive of, and not in addition to, any deposit required by any other state to be made for the benefit of all policyholders in the United States. This section shall not apply to any company unless such company or its predecessor or predecessors, if any, prior to merger or consolidation shall have been actively engaged in the insurance business in one or more states of the United States continuously for ten or more years; provided, that any foreign mutual company hereinbefore referred to which has not itself or through its predecessor or predecessors been so engaged in the insurance business continuously for ten or more years may issue non-assessable policies if it has and maintains a surplus to policyholders of not less than one million dollars. A company issuing a non-assessable policy under authority of this section may state therein, or on the filing back thereof, or in both such places, that such policy is non-assessable.