By Richa Naidu
(Reuters) - A former JPMorgan Chase & Co executive fighting U.S. extradition from Spain for allegedly helping to hide more than $6.2 billion in trading losses has filed a claim against Britain's financial regulator.
Javier Martin-Artajo, who oversaw an ex-JPMorgan trader nicknamed the "London Whale" for his large bets on derivatives markets, filed the claim against the Financial Conduct Authority (FCA) at a tribunal in London on March 12, according to the court's website. (http://link.reuters.com/saj77v)
Details about the case were not available and no hearing date has been set.
The "London Whale" scandal has cost America's largest bank $920 million in penalties from U.S. and British regulators so far, including the U.S. Securities and Exchange Commission and the FCA.
Neither the FCA nor Martin-Artajo's lawyer could be reached for immediate comment.
(Reporting by Richa Naidu in Bangalore; Editing by Tom Brown)