Independent professional managers shall be selected by the Board of Directors to manage and invest the assets of the corporation in accordance with such investment policies and guidelines as the Board of Directors of the corporation may adopt from time to time. Such investment managers shall be institutions of national size, stature, and capability, selected on the basis of performance record and fees. Except in the case of interests in local businesses contributed to the corporation, the assets of the corporation shall not be invested in local businesses, as determined by the Board of Directors of the corporation.