12 U.S.C. § 333

Any mutual savings bank having no capital stock (including any other banking institution the capital of which consists of weekly or other time deposits which are segregated from all other deposits and are regarded as capital stock for the purposes of taxation and the declaration of dividends), but having surplus and undivided profits not less than the amount of capital required for the organization of a national bank in the same place, may apply for and be admitted to membership in the Federal Reserve System in the same manner and subject to the same provisions of law as State banks and trust companies, except that any such savings bank shall subscribe for capital stock of the Federal reserve bank in an amount equal to six-tenths of 1 per centum of its total deposit liabilities as shown by the most recent report of examination of such savings bank preceding its admission to membership. Thereafter such subscription shall be adjusted semiannually on the same percentage basis in accordance with rules and regulations prescribed by the Board of Governors of the Federal Reserve System. If any such mutual savings bank applying for membership is not permitted by the laws under which it was organized to purchase stock in a Federal reserve bank, it shall, upon admission to the system, deposit with the Federal reserve bank an amount equal to the amount which it would have been required to pay in on account of a subscription to capital stock. Thereafter such deposit shall be adjusted semiannually in the same manner as subscriptions for stock. Such deposits shall be subject to the same conditions with respect to repayment as amounts paid upon subscriptions to capital stock by other member banks and the Federal reserve bank shall pay interest thereon at the same rate as dividends are actually paid on outstanding shares of stock of such Federal reserve bank. If the laws under which any such savings bank was organized be amended so as to authorize mutual savings banks to subscribe for Federal reserve bank stock, such savings bank shall thereupon subscribe for the appropriate amount of stock in the Federal reserve bank, and the deposit hereinbefore provided for in lieu of payment upon capital stock shall be applied upon such subscription. If the laws under which any such savings bank was organized be not amended at the next session of the legislature following the admission of such savings bank to membership so as to authorize mutual savings banks to purchase Federal reserve bank stock, or if such laws be so amended and such bank fail within six months thereafter to purchase such stock, all of its rights and privileges as a member bank shall be forfeited and its membership in the Federal Reserve System shall be terminated in the manner prescribed in this subchapter with respect to State member banks and trust companies. Each such mutual savings bank shall comply with all the provisions of law applicable to State member banks and trust companies, with the regulations of the Board of Governors of the Federal Reserve System and with the conditions of membership prescribed for such savings bank at the time of admission to membership, except as otherwise hereinbefore provided with respect to capital stock.