The transferee of a negotiable document has a specifically enforceable right to have his transferor supply any necessary endorsement but the transfer becomes a negotiation only as of the time the endorsement is supplied.
Delivery without endorsement; right to compel endorsement
Va. Code Ann. § 8.7-506, under Part 5. Warehouse Receipts and Bills of Lading: Negotiation and Transfer..
Va. Code Ann. § 8.7-506