BitMEX and its co-founders are facing a new class action lawsuit filed just one day after the crypto derivatives exchange announced its shutdown. The lawsuit alleges the exchange secretly traded against its own users through an internal trading desk, with plaintiffs BKX Services Inc. and David Namdar claiming combined losses of 622.66 BTC (approximately $40.7 million). The case adds to a long line of legal challenges for the exchange, which was once the dominant venue for crypto leveraged trading and pioneered the perpetual swap contract that has since become an industry standard across major exchanges.

BitMEX, Founders Named in New Class Action

The lawsuit was filed on July 23, 2026, in the U.S. District Court for the Southern District of New York by BKX Services Inc. and David Namdar on behalf of a proposed class of BitMEX users.

The complaint names HDR Global Trading Limited, along with BitMEX co-founders Arthur Hayes, Ben Delo, Samuel Reed, and former executive Gregory Dwyer as defendants. The plaintiffs allege the exchange secretly operated what the filing calls an "Insider Trading Desk" that traded directly against customers while publicly presenting itself as a neutral marketplace.

According to the complaint, BitMEX had privileged access to customer orders, including so-called "hidden orders," giving insiders an unfair trading advantage that ordinary users could not see. The lawsuit claims customers believed they were trading only against other market participants when, in reality, BitMEX itself was allegedly taking the opposite side of trades.

Complaint Alleges Hidden Trading Desk Profited From Customer Liquidations

A central allegation is that BitMEX used the internal desk to profit from customer liquidations while generating additional trading fees. According to the court filing, the exchange earned more than $1 billion in transaction fees between November 2014 and October 2024, while its flagship XBTUSD perpetual contract processed over $2 trillion in trading volume during that period.

The plaintiffs claim they suffered significant Bitcoin losses while trading on the platform. BKX Services alleges losses totaling 305.80903296 BTC, while David Namdar claims losses of 316.85578220 BTC through multiple liquidations. The complaint further alleges that customers collectively lost thousands of Bitcoin as a result of the exchange's conduct.

The lawsuit also revisits the March 13, 2020 market crash, claiming that approximately $800 million worth of leveraged positions were liquidated while many users were unable to access the exchange due to system outages. According to the complaint, the alleged insider trading operation continued functioning during the disruption. The filing argues that these events allowed BitMEX to generate what it describes as "ill-gotten gains" through trading fees, customer liquidations, and its growing Insurance Fund.

Plaintiffs Seek Return of Bitcoin

The plaintiffs are asking the court to certify the case as a class action and order BitMEX to return customers' Bitcoin. They are also seeking compensatory and punitive damages, legal fees, court costs, and interest. According to the complaint, users would not have traded on BitMEX had they known about the alleged hidden trading desk.

The lawsuit comes just one day after BitMEX shut down its exchange. It also follows the platform's 2020 legal troubles, when U.S. regulators charged the company over anti-money laundering and Bank Secrecy Act violations — charges that resulted in a $100 million settlement with the CFTC and FinCEN and guilty pleas from Hayes, Delo, Reed, and Dwyer. This new case shifts the focus from compliance failures to how BitMEX allegedly handled customer trades internally, an area that has drawn increasing scrutiny across the crypto exchange sector as traders demand greater transparency around conflict-of-interest risks.