D.C. Code § 47-4461
The purchaser, transferee, or assignee ("purchaser") of all or a part of the inventory, furnishings, equipment, materials, or supplies ("property") of a business, pursuant to a sale, transfer, or assignment in bulk other than in the ordinary course of trade or business ("sale"), shall, at least 15 days before taking possession of or paying for the property, notify the Mayor by registered or certified mail. The notice shall identify the price, terms, and conditions of the sale, including a description of the property being sold, its location, and the identity of the seller, transferor, or assignor ("seller"). The notice is required whether or not the seller has represented to, or informed, the purchaser that it owes tax under this title, whether it has complied with § 28:6-104, or whether taxes are in fact owing.
D.C. Code § 47-4461