Section 15H. An entity that may invest pursuant to section 15A or the legal list may invest in the common stock of banking corporations and bank holding companies subject to the following conditions, limitations and requirements:

(i) in the common stock of a bank in stock form incorporated under the laws of and doing business within the commonwealth; provided, however, that there shall be no preferred stock outstanding; or, in the common stock of a federally chartered bank in stock form doing business within the commonwealth; provided, however, that there shall be no preferred stock outstanding; provided further, that state-chartered or federally-chartered bank shall be well capitalized under bank regulatory criteria;

(ii) in the common stock of a state-chartered bank or federally chartered bank doing business anywhere within the United States, which is a member of the federal reserve system and is well capitalized under bank regulatory criteria;

(iii) in the common stock of a bank holding company as defined in chapter 167A; provided, however, that the stock shall be received pursuant to an offer made by the bank holding company to exchange shares of its common stock for shares of a bank in stock form incorporated under the laws of the commonwealth or for shares of a federally-chartered bank doing business in the commonwealth; or provided, however, that the stock shall be received pursuant to a plan for the merger or consolidation of the bank with or into or the transfer, sale or exchange of property or of assets of the bank or with a bank in stock form incorporated under the laws of the commonwealth or a federally-chartered bank doing business in the commonwealth the stock of the bank, as the case may be, shall be at the time owned by the bank holding company;

(iv) in the common stock of a bank holding company as defined in said chapter 167A acquired otherwise than as set forth in the first paragraph or in the common stock of a bank holding company as defined in the federal Bank Holding Company Act of 1956, 12 U.S.C. 1841 et seq.; provided, however, that the holding company shall own 80 per cent or more of the voting stock of the qualifying bank; provided further, that if at any time after an investment in the common stock of the bank holding company, no bank of the holding company shall meet the requirements of clauses (iii) or (iv), the holding company's stock shall be disposed of within the reasonable time as the commissioner shall determine; and

(v) in the common stock of a company as defined in chapter 167A or in said federal Bank Holding Company Act of 1956; provided, however, that the banking institution or bank shall be the kind referred to in clauses (iii) or (iv) and the stock of the banking institution or bank represents at least 50 per cent of the company's assets at book value at the end of its fiscal year immediately preceding the date of investment or at the date of investment in the case of a newly formed company.