A British software engineer is suing the operator of crypto derivatives exchange BitMEX for the return of 324.8 BTC, alleging the platform conducted regulated trading activities in the UK without authorization from the Financial Conduct Authority.
Lewis Barber filed the claim against BitMEX operator HDR Global Trading in London's Commercial Court. According to the particulars of claim, the Bitcoin was valued at approximately £20.4 million on October 1, equivalent to about $27.2 million.
Details of the Trading Activity
Barber entered into approximately 2,294 trades on the exchange between 2018 and 2022 from five accounts. The claim challenges 1,053 trades that resulted in losses for Barber, all of which involved perpetual swaps—derivatives similar to futures contracts but without expiry dates.
The claim argues that these perpetual swaps constitute regulated activities that BitMEX was not authorized to carry out in the UK, and therefore cannot be enforced against Barber under the Financial Services and Markets Act 2000.
Regulatory Violations Alleged
The claim states that BitMEX did not restrict access from the UK, allowed new users to select it as their country of residence, and conducted promotional campaigns globally, including an advertisement in The Times in January 2019. The FCA issued a warning in March 2020 that BitMEX may have been trading regulated investments in the UK without authorization.
Barber also claims damages for deceit, alleging BitMEX knew it lacked authorization when it implicitly represented that it could lawfully trade with him. His solicitors sent a letter to BitMEX rescinding the trades in December 2025.
Broader Legal Implications
Legal experts suggest other UK-based traders may hold similar claims against BitMEX. According to Gareth Keillor, a partner at Seladore Legal representing Barber, the potential total of such claims could reach hundreds of millions of pounds, depending on individual trading histories and circumstances.
The claim has been filed but has not yet been formally served on BitMEX. A BitMEX spokesperson told The Guardian that no such claim has been served on HDR Global Trading Limited.
BitMEX's Regulatory History
BitMEX shut down on September 23, following an announcement in July that it would close operations. The exchange faces additional legal challenges, including a proposed class action in New York alleging theft of Bitcoin and insider trading, which names co-founders Ben Delo, Arthur Hayes, and Samuel Reed.
The three co-founders pleaded guilty in 2022 to violating the Bank Secrecy Act through anti-money laundering failures. They were pardoned by President Donald Trump in March 2025. BitMEX itself pleaded guilty to Bank Secrecy Act violations in 2024 and was ordered to pay $100 million in January 2025.
