A £20m claim over lost bitcoin is at the centre of a BitMEX UK lawsuit that challenges the legality of its derivatives sales. Software engineer Lewis Barber alleges the exchange offered those products without Financial Conduct Authority authorization and argues that he is entitled to recover his losses.
Key takeaways
Barber’s claim concerns bitcoin losses from 2018 to 2022.
The defendant is BitMEX operator HDR Global Trading Limited.
The lawsuit seeks restitution under UK financial services law.
BitMEX voluntarily closed on September 23, 2026.
According to The Guardian , the claim has been filed at the High Court but has not yet been served on the defendant. The exchange was founded by billionaire Ben Delo, whose record-breaking £36m donation to Reform UK has drawn attention in Britain. Decrypt’s coverage puts the bitcoin recovery sought at $27m.
The BitMEX UK lawsuit seeks repayment of trading losses
Barber is suing HDR Global Trading Limited , the owner and operator of BitMEX, for bitcoin he says he lost trading derivatives between 2018 and 2022. Those products amplified investors’ gains or losses as the cryptocurrency’s value changed.
His case argues that transactions entered into without the required authorization are void under the Financial Services and Markets Act 2000 . He seeks the return of the bitcoin lost through those trades, or equivalent damages.
Gareth Keillor, a partner at Seladore Legal representing Barber, said: “This is a substantial claim concerning losses sustained by Lewis over a number of years.” Keillor explained that the claim rests on the authorization required under UK law and the right to recover losses under the act.
A spokesperson for the exchange said: “No such claim has been served on HDR Global Trading Limited.”
FCA warning and UK advertising form part of the claim
Barber’s statement of claim cites an FCA warning issued on or around March 3, 2020 , concerning possible unauthorized trading in regulated investments in the UK. It also points to promotional activity that reached British investors.
The filing alleges that BitMEX ran worldwide campaigns without excluding the UK. It identifies at least one advertisement in The Times, published on January 3, 2019 , as part of its argument that the exchange promoted its services to UK investors without the required approval.
Barber’s lawyers allege that he may be among thousands of non-professional UK investors who suffered heavy losses on products sold in breach of FCA rules and consumer protection laws. Keillor qualified the broader relevance: any other person’s claim would depend on their individual circumstances and trading history.
Founders’ guilty pleas and the company’s US penalty
BitMEX and its founders have previously faced US proceedings over compliance with the Bank Secrecy Act . Delo and co-founders Arthur Hayes and Samuel Reed pleaded guilty in 2022 over alleged failures to comply with anti-money-laundering procedures.
The three received fines and non-custodial sentences. Donald Trump pardoned them in March 2025.
The company separately pleaded guilty in 2024 to Bank Secrecy Act violations involving inadequate anti-money-laundering and know-your-customer programmes. The US Department of Justice ordered the firm to pay $100m (£75m) in January 2025.
Closure and other legal actions
The Seychelles-based exchange voluntarily closed on September 23, 2026, following what it described as a strategic review. Details of the BitMEX UK lawsuit emerged after that closure.
Barber’s lawyers claim that, if his case succeeds, liabilities for the exchange could reach hundreds of millions of pounds. That is their assessment of the potential wider exposure, rather than an amount awarded by a court.
In New York, investors are also pursuing a multimillion-dollar class action alleging bitcoin theft and insider trading. Those allegations have been vigorously denied.
Article produced with the assistance of artificial intelligence and reviewed by the editorial team.
