Mike Lynch, the founder of software firm Autonomy, submitted himself for arrest as part of an extradition process initiated by authorities in the US.
Lynch was arrested at Charing Cross police station in London on Wednesday morning, and presented at Westminster Magistrates' Court where he was released on a £10 million bail.
In a statement, Lynch's lawyers said that the tech entrepreneur rejects all the accusations against him and added that he would continue to fight the charges - no doubt mindful of the five-year prison sentence handed down to the former Autonomy chief financial officer, Sushovan Hussain, in May last year.
"Dr Lynch is a British citizen who ran a British company listed on the London Stock Exchange, governed by English law and UK accounting standards. This extradition request reflects yet another example of the DOJ's attempts to exert extraterritorial jurisdiction over non-US conduct...
"The UK Serious Fraud Office previously investigated and did not pursue the allegations. Dr Lynch has now answered HP's claims in the appropriate forum, the High Court in London, where he attended court every day of the 10-month trial," Lynch's lawyers, Chris Morvillo and Reid Weingarten, said in a statement.
"The US Department of Justice should not have commenced extradition proceedings prior to the judgment of the English High Court," they added.
In November,the US Department of Justice asked the UK government to allow extraditionof Mike Lynch to face trial in a US court. That request was reiterated in December by the US Embassy in London.
Opposing Lunch's extradition, David Davis MP, the former Brexit secretary, urged the home secretary to block the extradition request until after the High Court in London has passed its final verdict in the civil fraud case against the tech entrepreneur.
Lynch faces charges of conspiracy, securities fraud and wire fraud related to thesale of Autonomy to Hewlett Packard (HP) in $11.1 billion dealin 2011.
A few months after the deal was closed, HP wrote down Autonomy's value by $8.8 billon, claiming that Lynch and Hussain had inflated Autonomy revenues to make the company look more valuable than it actually was.
HP called in the Serious Fraud Office (SFO) a year after the acquisition, and also filed a civil fraud case in London's High Court seeking damages of $5 billion from Lynch and Hussain. However, the SFO closed its criminal investigation in January 2015 claiming that there was "insufficient evidence".
In May, aUS jury sentenced Hussain five years in jailand $4 million fine after finding him guilty of doing conspiracy, wire fraud and securities fraud. He was also ordered to forfeit $6.1 million.
Lynch, however, denies any wrongdoing. He counter-sued HP and blamed it for the failed acquisition.
In the British High Court, he accused HP of treating Autonomy like its "unwanted stepchild," and said that the company had "failed to follow any coherent integration for Autonomy".
He stressed that Autonomy was "one of the most successful companies England has ever produced" and that Meg Whitman, the ex-CEO of HP, "could not cope with all the fires" at the company.
He claimed that HP tried to make him a "scapegoat" after Whitman failed to integrate Autonomy.
Arguments in the UK trial concluded in January, and a final judgement is expected in coming months.
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