Mike Lynch has resigned as an adviser to Darktrace, the London-listed cybersecurity company, a week after Priti Patel ordered the former Autonomy boss’s US extradition to face criminal charges.

Mr Lynch, 56, has stepped down from Darktrace’s science and technology committee, the company confirmed on Friday.

He has also resigned from Luminance, the legal artificial intelligence start-up backed by his venture capital firm Invoke.

Mr Lynch, who founded Autonomy in 1996, has spent years fighting fraud allegations over the former FTSE 100 company’s $11bn (£8bn) sale to Hewlett Packard in 2011.

He suffered a double legal blow last week when a judge ruled against him in a $5bn (£3.7bn) fraud case brought by HP, and hours later, the Home Secretary approved his extradition to the US to face criminal fraud charges over Autonomy’s sale.

Lawyers for Mr Lynch have said he will appeal in both cases.

Mr Lynch, Darktrace’s founding investor, stepped down from the company’s board in 2018 when he was first charged but remained on its science and Technology Committee. He also resigned as a government adviser, left a role at the Royal Society, and left the board of Sophia Genetics, another Invoke investment.

He remains Darktrace’s second largest shareholder through stakes owned by him and his wife, valued at around £400m, while Invoke has a seat on its board. However, his departure means he now has no formal role.

Luminance, which was valued at $100m in a fundraising round in 2019, uses artificial intelligence to sift through documents and discover anomalies.

Lawyers for Mr Lynch are currently poring over a draft verdict from the High Court in the civil case brought by HP before it is made public in the coming weeks. Last week the court said HP had “substantially succeeded” in its claim that Mr Lynch and former Autonomy finance chief Sushovan Hussain inflated the company’s revenues ahead of its sale.

Mr Lynch is facing 17 counts of fraud related to the sale in the US and denies the charges but has been battling attempts to extradite him. He is preparing an appeal that is likely to see him remain in the UK for several months at least.

A Luminance spokesman said: “We can confirm that Mike Lynch offered to step down from the board whilst he focuses on fighting his appeals and clearing his name. Dr Lynch has been an invaluable advisor to Luminance and we thank him for his contribution. We are pleased to have another Invoke partner, Charlotte Golunski, join the board of directors and welcome Invoke’s continued support for the business.”

An Invoke spokesman said: “Dr Lynch has stepped down from all his official roles to focus on the anticipated appeals in his legal cases and the ongoing battle to clear his name.”