Mass. Gen. Laws ch. 106, § 7-403
(a) A bailee shall deliver the goods to a person entitled under a document of title if the person complies with subsections (b) and (c), unless and to the extent that the bailee establishes any of the following:
(c) Unless a person claiming the goods is a person against which the document of title does not confer a right under subsection (a) of section 7–503: