R.I. Gen. Laws § 19-9-15: Pledge of passbook accounts.

Any deposit evidenced by a passbook in a regulated institution may be pledged by delivery of the passbook to the pledgee, with an order for its transfer; but this pledge shall not be effective to secure the deposit against any person other than the pledgor or his or her executor or administrator, unless an actual transfer of the deposit has been made upon the books of the regulated institution or the order for the transfer has been disclosed to, and a copy filed with, the regulated institution holding the deposit.