-165§ 1812. Negotiation of negotiable receipts by indorsement A negotiable receipt may be negotiated by the indorsement of the person to whose order the goods are, by the terms of the receipt, deliverable. The indorsement may be in blank, to bearer, or to a specified person. If indorsed to a specified person, it may be again negotiated by the indorsement of that person in blank, to bearer, or to another specified person. Subsequent negotiation may be made in like manner. § 1813. Transfer of receipts A receipt which is not in such form that it can be negotiated by delivery may be transferred by the holder by delivery to a purchaser or donee. A nonnegotiable receipt may not be negotiated, and the indorsement of such a receipt gives the transferee no additional right. § 1814. Who may negotiate a receipt A negotiable receipt may be negotiated by any person in possession of it, however possession may have been acquired, if, by the terms of the receipt, the warehouseman undertakes to deliver the goods to the order of that person or if at the time of negotiation the receipt is in such form that it may be negotiated by delivery. § 1815. Rights of person to whom a receipt has been negotiated A person to whom a negotiable receipt has been duly negotiated acquires thereby: (1) such title to the goods as the person negotiating the receipt to him had or had ability to convey to a purchaser in good faith for value, and also such title to the goods as the depositor or person to whose order the goods were to be delivered by the terms of the receipt had or had ability to convey to a purchaser in good faith for value; and (2) the direct obligation of the warehouseman to hold possession of the goods for him according to the terms of the receipt as fully as if the warehouseman had contracted directly with him. § 1816. Rights of person to whom a receipt has been transferred A person to whom a receipt has been transferred but not negotiated acquires thereby, as against the transferor, the title to the go(Ss, subject to the term of any agreement with the transferor. If the receipt is nonnegotiable, the person also acquires the right to notify the warehouseman of the transfer to him of the receipt, and thereby to acquire the direct obligation of the warehouseman to hold possession of the goods for him according to the terms of the receipt. Prior to the notification of the warehouseman by the transferor or transferee of a nonnegotiable receipt, the title of the transferee to the goods and the right to acquire the obligation of the warehouseman may be defeated by the levy of an attachment or execution upon the goods by a creditor of the transferor, or by a notification to the warehouseman by the transferor or a subsequent purchaser from the transferor of a subsequent sale of the goods by the transferor. § 1817. Transfer of negotiable receipt without indorsement If a negotiable receipt is transferred for value by delivery, and the indorsement of the transferor is essential for negotiation, the transferee acquires a right against the transferor to compel him to indorse the receipt, unless a contrary intention appears. The negotiation takes effect as of the time when the indorsement is actually made.