Sec. 507. If a person negotiates or delivers a document of title for value, otherwise than as a mere intermediary under section 508 of this chapter, unless otherwise agreed, the transferor, in addition to any warranty made in selling or leasing the goods, warrants to its immediate purchaser only that:
(1) the document is genuine;
(2) the transferor has no knowledge of any fact that would impair the document's validity or worth; and
(3) the negotiation or delivery is rightful and fully effective with respect to the title to the document and the goods it represents.