All public utility or other investments of money of the bank permitted or provided for under this chapter shall at all times be purchased and held in fully marketable form, subject to provision for any registration in the name of the bank. All public utility bonds at any time purchased, held or owned by the bank shall upon delivery to the bank be accompanied by documentation, including approving legal opinion, certification and guaranty as to signatures, certification as to absence of litigation and such other or further documentation as shall from time to time be required in the municipal bond market.   [PL 1987, c. 141, Pt. A, §6 (NEW).]