The family of Stephen Chamberlain, the co-defendant in the US trial of missing tycoon Mike Lynch, said he would be “deeply missed” after he was hit by a car and died at the weekend.
Cambridgeshire Police said 52-year-old Mr Chamberlain died in hospital after he was struck by a car in Stretham on Saturday.
A statement from his lawyer said he was hit “while out running”.
It comes as Mr Lynch was confirmed as one of the six tourists missing on Monday after the Bayesian luxury yacht sank in a tornado off the coast of Sicily.
Mr Chamberlain was cleared earlier this year, alongside Mr Lynch, of conducting a massive fraud over the sale of software company Autonomy to Hewlett-Packard (HP) in 2011.
Relatives of Mr Chamberlain said in a tribute released through police that he was a “much-loved husband, father, son, brother and friend”.
“He was an amazing individual whose only goal in life was to help others in any way possible,” his family said.
“He made a lasting impression on everyone who had the privilege of knowing him.
“He will be deeply missed but forever in the hearts of his loved ones.”
Cambridgeshire Police are appealing for witnesses after Mr Chamberlain – a pedestrian – was in collision with a blue Vauxhall Corsa car on the A1123 Newmarket Road in Stretham.
The force said the car was travelling between Stretham and Wicken when the collision happened at about 10.10am on Saturday.
Mr Chamberlain was taken to hospital with serious injuries and later died.
Police said the driver of the car, a 49-year-old woman from Haddenham, remained at the scene and was assisting with inquiries.
She has not been arrested.
Gary Lincenberg, Mr Chamberlain’s lawyer, said in an earlier statement: “Our dear client and friend Steve Chamberlain was fatally struck by a car on Saturday while out running.
“He was a courageous man with unparalleled integrity. We deeply miss him.
“Steve fought successfully to clear his good name at trial earlier this year, and his good name now lives on through his wonderful family.”
HP acquired Cambridge-based Autonomy, founded by Mr Lynch in 1996, for 11 billion US dollars, but later wrote down its value by 8.8 billion US dollars and asked the US justice department to investigate fraud.
Mr Chamberlain, a former vice-president of finance at the company, was accused of artificially inflating Autonomy’s revenues and making false and misleading statements to auditors, analysts and regulators in 2018.
Both he and Mr Lynch were found not guilty of the charge in June following a trial at a federal court in San Francisco, California.
Mr Chamberlain was former chief operating officer of the British cybersecurity company Darktrace, which was founded in 2013 and is headquartered in Cambridge.
A Darktrace spokesperson said in a statement: “We are incredibly saddened to hear of the tragic death of Steve Chamberlain, Darktrace’s former chief operating officer and a substantial contributor to the team in its early years.
“Steve was much loved by his colleagues and leaves many friends at Darktrace.
“We extend our deepest condolences to his wife, Karen, and the rest of his family who are very much in our thoughts at this challenging time.”
Mr Lynch was previously made an OBE for services to enterprise in 2006.
The British-flagged superyacht, named Bayesian, capsized at about 5am local time off the coast of Palermo on Monday when the area was hit by a tornado.
Anyone with information or dashcam footage of the collision in Stretham, Cambridgeshire, or of the moments before or after, is asked to contact police.
People are asked to call 101 and request to speak with Detective Constable Kevin Drury in the serious collision investigation unit.