Mike Lynch, who was reported missing after his yacht sank in a storm off the coast of Sicily, has experienced some of the most extreme highs and lows of any British technology entrepreneur in his career.

Lynch, a self-made man in the software industry, became a prominent investor and vocal advocate of the British tech start-up scene. The sale of his company Autonomy to Hewlett-Packard in 2011 for $11 billion was the largest sale of a European IT group at the time and cemented his position as one of the few bosses of a British tech company to make it onto the world stage.

But a year later, HP claimed that Autonomy executives had fraudulently inflated the value of the acquisition by $5 billion, leading to a 12-year legal battle. Lynch lost a long battle against extradition to the US on fraud charges and spent more than a year under house arrest in San Francisco before his trial. He was finally acquitted of all charges by a jury in June of this year.

Lynch, 59, was among those missing after the yacht Bayesian, officially owned by his wife, sank in heavy weather in the Mediterranean early Monday morning.

Six of the 12 passengers and 10 crew members on board were declared missing, including Lynch’s 18-year-old daughter Hannah, while one crew member died. Among the passengers were members of Lynch’s legal team and a defense witness he had invited to celebrate his victory in court.

The long journey that led Lynch to own a 56-metre luxury superyacht began in humble circumstances. Born in Ilford, Essex, and raised in nearby Chelmsford, he spoke readily of the hardships of his childhood. Giving evidence at this year’s trial, he said that as the son of Irish parents he was something of an outsider, particularly during the political turmoil of the 1970s when “there were times when you had to learn to run fast”.

He won a scholarship to Bancroft’s, a private school in Woodford, Essex, but claimed he shunned the trappings of social status. He told the jury that his first job was sweeping floors at a local hospital and said: “As a 16-year-old… you realise that what you want to do, you just have to do it.”

Lynch went on to study science at Christ’s College, Cambridge University, and later gained a PhD in signal processing, specialising in a technique used in areas such as mobile communications to separate the signal from the noise in digital data. In the late 1980s, he began to use his expertise in entrepreneurial terms with a series of start-ups, the first of which was to develop a device for sampling music.

He founded Autonomy in 1996, just as an explosion of digital data was beginning to flood corporations and other large organizations. Sorting through unstructured data, or information that was not stored in easily searchable databases, presented enormous challenges. The sale to HP confirmed Lynch’s success in gaining a globally recognized position in one of the most strategically important technologies of the time.

However, HP CEO Meg Whitman accused Autonomy’s executives of falsely inflating the company’s revenue in the years before the sale through tricks such as “round-trip deals,” in which Autonomy paid its customers money when they bought its software. Lynch jumped to his defense in the years that followed, turning the fight into a personal feud with Whitman, whom he accused of fabricating the fraud allegation to cover up her own mismanagement of the struggling US technology company.

Autonomy’s former chief financial officer, Sushovan Hussain, was convicted in the U.S. in 2019 of fraud related to the sale of Autonomy, and HP won a civil fraud lawsuit against Lynch in the U.K. in 2022. Despite these victories, U.S. prosecutors stumbled in trying to prove that Lynch, as the company’s CEO, was criminally liable for the alleged fraud.

The jury was presented with two very different versions of the software chief. The prosecution portrayed him as a domineering micromanager, while the defense portrayed him as a technology strategist who saw the big picture and paid no attention to the complex accounting issues at the heart of the fraud charges.

“I’m not an accountant… and I’m not a salesman,” Lynch said, successfully convincing the jury that he was unfamiliar with the convoluted financial transactions presented in court. “I sat there and watched a parade of witnesses I’d never met… and a series of transactions I had no involvement in, and not much else.”

Although he was ultimately acquitted, the charges cast a long shadow over Lynch’s career in the US. In addition to a personal fortune – he earned more than $800 million from his stake in the company – Autonomy had previously given him a platform to advocate for the causes of technology start-ups and to play a prominent role in public life.

Lynch was a non-executive director of the BBC and a member of Prime Minister David Cameron’s Science and Technology Council, where he advised on the importance of the coming wave of artificial intelligence. In 2006 he was awarded the OBE for services to business.

After he was indicted in the U.S. in 2018, he stepped back from many of his public offices, but continued to invest through Invoke Capital, the venture capital firm he founded after the sale to HP.

In his first public comments since the trial, Lynch recently told the Sunday Times that he wanted to support people who had been wrongly convicted and fight against what he saw as unjust extraditions, such as the one that forced him to stand trial in the United States.

“The system can drag individuals along,” he said. “There has to be an opposing option that says, ‘Well, the whole world thinks you’re guilty, but was that even a fair conviction?'”