Section 69A. An association or trust which owns all of the capital stock of a company may be merged into such company. Such company and such association or trust shall enter into an agreement in writing which shall prescribe the terms of the merger. Such agreement shall be approved by unanimous vote of each class of stock of said company at a meeting called for the purpose and for which notice of meeting is waived. Such agreement shall be approved by affirmative vote by such association or trust in the manner provided in the written instrument or declaration of trust under which such association or trust was formed or is regulated. Within thirty days after the meeting at which such merger has been voted, articles of amendment setting forth (1) said vote, (2) a copy of the agreement for said merger, and (3) a certificate that all of the stock of the company is owned by the association or trust certified by the president, treasurer and a majority of the directors of the company and by the persons authorized to execute said agreement for the association or trust shall be submitted to the department for approval. Within thirty days after such approval, the documents filed with the department, together with a certified copy of the order of the department approving the proposed merger shall be filed with the state secretary accompanied by a fee to be determined annually by the commissioner of administration under the provisions of section three B of chapter seven. The state secretary shall examine such articles of amendment and, if he finds that they conform to the provisions of the law relative to the merger of companies and associations or trusts, he shall so certify and endorse his approval thereon. No merger shall take effect until the articles of amendment have been filed as aforesaid. Upon the filing of such articles, all of the property, real, personal and mixed of the merged association or trust shall vest in and be held and owned by the company as the same were before held and owned by the merged association or trust.