Mass. Gen. Laws ch. 203B, § 11: Third person dealing with one purporting to act as trustee

Section 11. A third person in good faith and without a court order may act on instructions of, or otherwise deal with, a person purporting to make a transfer as, or purporting to act in the capacity of, a custodial trustee. In the absence of knowledge to the contrary, the third person shall not be responsible for determining:

(1) the validity of the purported custodial trustee's designation;

(2) the propriety of, or the authority under this chapter for, any action of the purported custodial trustee;

(3) the validity or propriety of an instrument executed or instruction given pursuant to this chapter either by the person purporting to make a transfer or declaration or by the purported custodial trustee; or

(4) the propriety of the application of property vested in the purported custodial trustee.