The obligation arose from a transaction that occurred nearly 20 years before the bankruptcy filing, whereby the Debtor purchased from the counterparty under an Asset Purchase Agreement (APA) certain assets relating to the counterparty's Acthar Gel product, including trademarks, the New Drug Application for Acthar Gel, inventory, and know-how (collectively, the "Acthar Gel IP") in exchange for a $100,000 up-front payment and a perpetual 1% royalty of all annual net sales of Acthar Gel in excess of $10 million per year. Critically, the counterparty received a purchase money security interest in the Acthar Gel IP to secure the $100,000 payment, but not the perpetual royalty. The drug was incredibly successful, with annual sales hitting almost $1 billion by 2019.