Lynch, 59, became a British success story after selling his software startup Autonomy to HP for more than $11 billion in 2011.
But HP soon accused Autonomy's bosses of fraudulently inflating the company's revenues to boost the acquisition price, sparking a 12-year legal battle for Lynch.
The latest trial ended in June with a jury acquitting Lynch of all charges.
Here's a closer look at the Lynch's colorful life.
Michael Richard Lynch was born in Essex, UK on June 16, 1965.
Wikipedia / CC 3.0
He had humble beginnings: his mother was a nurse and his father was a fireman.
Lynch said that his father regretted not having the chance to go to university. "He realized the importance of education so that was something that was very much fostered in my home," Lynch told LeadersIn.
When he was 11 years old, he won a scholarship to study at Bancroft's School in Woodford, Essex. Today, for those not on a scholarship, the senior school charges around £21,000 or $27,000 per student per year.
YouTube/Bancroft's School
Lynch, pictured in the centre of this five-piece jazz band, was interested in music from a young age.
Mike Lynch
Lynch got his first taste of management from running a band in his early 20s. The name of the band isn't known.
After school, Lynch went to the University of Cambridge to study natural sciences. During his course, he combined mathematics with biological and physical sciences.Christ's College, Cambridge.
Wikimedia Commons
Lynch also studied electrical sciences as part of his degree. His interest in electrical sciences led him to meet Peter Rayner, who became his mentor in the signal processing laboratory at Cambridge's engineering department.
YouTube/Centre for Computing History
After graduating, Lynch went on to complete a PhD at Cambridge in signal processing and communications research. It was titled: "Adaptive techniques in signal processing and connectionist models."
Toward the end of the 80s, Lynch founded a company called Lynett Systems Ltd.Lynch designing and making synthesizer prototypes in 1986.
Mike Lynch
The company produced designs and audio products for the music industry. One invention included a sampler for the Atari ST known as the Lynex. That was followed by the ADAS sampler for Atari, Mac, and PC.
In 1991, Lynch founded Cambridge Neurodynamics — a tech company that focused on computer-based fingerprint recognition.Lynch (left) went to Hungary to sell his fingerprint machines in 1994.
Mike Lynch
Lynch also sold some of his fingerprint machines to South Yorkshire Police.
Mike Lynch
But Lynch decided to focus his efforts on software. He cofounded search software firm Autonomy in 1996 with David Tabizel and Richard Gaunt as a spinoff from Cambridge Neurodynamics. Autonomy would go on to be one of the UK's biggest tech companies.Mike Lynch, Founder and Chairman of Autonomy Corporation, poses for photographers at an awards ceremony in central London
Thomson Reuters
Autonomy's first attempt to commercialize its technology was in a consumer product. It featured a virtual dog that would take commands to help internet users manage information.
However, soon after it launched, corporates started buying the technology in large numbers.
This, coupled with the emerging trend of free consumer products online, was enough to persuade Lynch to shift toward concentrating on corporates. It was a key strategic move for Autonomy.
Autonomy's software could also be used to sift through emails in place of humans, and the company's pattern-matching algorithms could abstract meaning from a jumble of information.
Lynch's beloved otterhound, Gromit (not pictured), became famous when it featured in some of Autonomy’s earlier products.
Wikimedia Commons
Autonomy went public in 1998 with shares priced at 30p each.Soap bubbles float past St Paul's Cathedral in central London, Britain April 17, 2017.
REUTERS/Stefan Wermuth
Autonomy witnessed the full power of the dot-com boom (and subsequent bust) when its shares climbed to over £30 in the late 90s before falling to under £1 when the bubble burst in 2000/2001.
Lynch told The Telegraph that managing a company through such tumultuous swings provided great training.
"It was like the Wild West back then for volatile stocks," he said. "All sorts of things went on that don't go on these days. It was very good training, you learn how to deal with quite outrageous situations."
In May 2007, Autonomy bought video search engine Blinkx from Suranga Chandratillake, who previously worked at Autonomy as CTO. Autonomy floated Blinkx in a stock market listing that valued the company at $250 million (£193 million).Suranga Chandratillake.
Balderton
Chandratillake told Business Insider: "Mike is a uniquely talented entrepreneur, especially within the European ecosystem. It's rare to find someone who is a PhD in data science but also a visionary product marketer and talented organization builder.
"I learned a great deal about business, product, marketing and the competitive element that is at the core of really successful organizations through the opportunity I had working for him as Autonomy's US CTO. Years later when he sold the company to HP, I wasn't surprised that it was the largest AI exit ever and one of the top three technology exits from Europe in history."
Autonomy made a number of other sizable acquisitions including: search software rival Verity ($500 million, December 2005); email archiving and litigation support company Zantaz ($375 million, July 2007); records management software firm Meridio Holdings (£20 million, October 2007); enterprise content management firm Interwoven ($775 million, January 2009); and online backup provider Iron Mountain Digital ($380 million, May 2011).
In October 2011, Lynch sold Autonomy to Hewlett-Packard for $11.7 billion (£8.7 billion) as the US tech giant looked to focus on software. Léo Apotheker was HP's CEO at the time but he was fired by the board as the controversial deal went through.Ex-HP CEO Leo Apotheker.
AP
The acquisition turned out to be highly controversial and many of HP's shareholders claimed that HP had overpaid at the time.
In September 2011, Apotheker was replaced by former eBay CEO Meg Whitman. She remained committed to the Autonomy deal but she and Lynch didn't always see eye-to-eye.HP CEO Meg Whitman.
HP
In November 2012, HP announced an $8.8 billion writedown related to the Autonomy acquisition, with $5 billion due to alleged "accounting irregularities" that led HP to massively overpay for Autonomy. That same month, investors started taking legal action against HP based on how it handled the deal.
Around the same time, auditing giant Deloitte, which had been involved in the acquisition, came out in support of Lynch and Autonomy.
HP's legal battle with investors lasted two years before the firm won the right to settle out of court in March 2015, leaving it free to pursue Mike Lynch.
Ken Wolter/Shutterstock
HP sued Lynch that same month for $5.1 billion in the UK's High Court.Meg Whitman, the former CEO of Hewlett-Packard.
AP Photo/Richard Drew
This court case has resulted in a wider spaghetti of legal entanglements between HP and Autonomy's former executives.
In its filings to the UK High Court case, HP unveiled full details of the acquisition. It said that Lynch inflated revenues by $700 million (£541 million) over a two-and-a-half-year period.
After writing off three-quarters of Autonomy's value, HP sold what was left of the company to British firm Micro Focus in September 2016 as part of an $8.8 billion (£6.8 billion) deal that involved other HP business units.
Just to confuse things further, Lynch counter-sued HP in October 2015 for more than $150 million.The Royal Courts of Justice, London.
Getty
In October 2015, Lynch counter-sued HP in London's High Court for more than $150 million (£116 million) over the allegations of massive fraud it against him. Lynch accused Whitman of trashing his reputation and hampering his venture capital fundraising efforts.
In the meantime, Lynch planned a $1 billion (£770 million) fund called Invoke Capital to invest in fundamental European technologies.
YouTube/TechCrunch
Commenting on the fallout between HP and Autonomy at TechCrunch Disrupt in 2016, Lynch said: "It's a sad thing that happened in the end."
He added: "The UK model is there's no way of stopping a takeover. So when Hewlett Packard came along and wanted to make its offer, we couldn't stop them. The people that were doing it at the time, Leo and Shane (head of strategy), had an amazing strategy. What they wanted to do was to take the company, refocus it into this new age of big data and software and machine intelligence and that was exciting and we got convinced by them.
"We could see the future was that way. The problem was the week after the deal they get fired and we're left with a hardware group that used to call us the stepchild. All the understanding of clever, high growth, software people wasn't there."
Darktrace developed software that helps organizations detect intruders on their network.
Darktrace
The company's technology, which can spot unusual email activity and suspicious file uploads, is underpinned by complex maths that was developed at Cambridge University.
"The reason I liked it was that it was a completely new approach," Lynch told Business Insider in 2016. "Most of what's out there in cybersecurity is based on knowing what you're looking. So things like anti-virus and that sort of stuff or trying to build a big wall around the outside of your company, a boundary.
"The problem is that the world's moved on and the attacks no longer have signatures. You can get kits that make attacks that don't look like anything that's been done before. But also every day you allow loads of people to walk through your wall and so the wall is pretty porous. The reality I was familiar with from some of my other roles as directors of large companies is that it's very, very hard to keep stuff out. The reality is almost every company is infiltrated. So you have to take a different approach. You have to do it much more like an immune system."
Lynch's successes were overshadowed by the Autonomy lawsuits. Former CFO Sushovan Hussain was charged with fraud in April 2018.Sushovan Hussain
Autonomy
A US jury found former Autonomy CFO Sushovan Hussain guilty of fraud. They found he had played a key part in the takeover by HP, which boosted his own wealth by $7.7 million.
Hussain was sentenced in 2019 to five years in prison.
Mike Lynch was later charged with fraud and lost a long battle against extradition to the US.
REUTERS / Jonathan Ernst
The US Department of Justice filed 14 charges of fraud and conspiracy against Lynch in November 2018. The charges carried a maximum penalty of 20 years in prison, and US prosecutors wanted to see Lynch give up the $815 million he made from the Autonomy sale.
Following the charges, Lynch stepped back from his public activities. He stepped down from the board of Darktrace, and as an advisor to the Royal Society and the government.The Royal Society on Pall Mall in London.
Wikimedia Commons
The Sunday Times once referred to Lynch as "Britain's Bill Gates," while The Financial Times called him "the doyen of European software."Microsoft cofounder Bill Gates.
Ramin Talaie/Getty Images
Lynch keeps red poll cattle and other rare animal breeds at his home in Suffolk.
Wikimedia Commons
"I keep rare breeds," Lynch told Leaders In in an interview uploaded to YouTube. "So I have cows that became defunct in the 1940s and pigs that no one has kept since the medieval times and none of them have any Apple products whatsoever."
HP won a fraud claim against Lynch in the UK in 2022, but Lynch was cleared of all charges by a US jury in June 2024.Mike Lynch is a director and early investor at Darktrace.
Ben Gurr/WPA Pool/ Getty Images
Mike Lynch is missing after a superyacht disaster in the Mediterranean.
HENRY NICHOLLS/Reuters
Mike Lynch's whereabouts are unknown after his family superyacht sank off the coast of Sicily on Monday.
He and his 18-year-old daughter are among the six passengers and 10 crew members who've been declared missing after a violent storm capsized Bayesian, their sailing vessel. Authorities are continuing to search for them.