D entered into a brokerage services agreement with P. D was obligated to provide prime brokerage services by clearing and settling trades in fixed income securities for P. D then entered into a credit default swap agreement with Citibank, N.A. (Citibank). D alleges that it was a “customer” of P, which allegedly acted as the middleman culminating in the credit default swap agreement with Citibank. Citibank eventually declared a write-down of the assets covered in its credit default swap agreement triggering D's obligation to pay Citibank a total of $10,000,000. D sued Citibank, seeking a declaration that, by declaring the write-down, Citibank had violated the terms of the parties' credit default swap agreement. The district court found D was in breach of the agreement by failing to fulfill its payment obligation. D also began arbitration proceedings against P before the FINRA. P filed a complaint in the district court to permanently enjoin the arbitration and for a declaration that P had no obligation to arbitrate with D regarding the claims submitted to the FINRA arbitrators. P moved for a temporary restraining order and preliminary injunction against the FINRA arbitration. P asserted that it was not a party to, and did not broker, the credit default swap and thus not a customer and was under no obligation to arbitrate. D submitted a declaration that “P recommended and set the terms for” the credit default swap and that D's employees had “dealt with several P representatives in connection with the transaction, but most often with Jeff Gapusan, Donald Quintin, and Jaime Aldama.” The district court granted P's motion for a preliminary injunction under the standard where the movant is required to show “‘irreparable harm absent injunctive relief, and either a likelihood of success on the merits, or a serious question going to the merits to make them a fair ground for trial, with a balance of hardships tipping decidedly in plaintiff's favor.’ P raised “serious questions” as to whether D was, in fact, a customer granted the preliminary injunction on that basis. This appeal eventually resulted.