A cruise on the Mediterranean Sea aboard a superyacht was supposed to be a celebratory event for the British tech entrepreneur Mike Lynch, who was acquitted in June of fraud charges tied to the sale of his company, Autonomy, to the tech giant Hewlett-Packard.

Instead, it turned into a disaster after the yacht, a 180-foot boat called the Bayesian, sank off the coast of Sicily in a violent storm. Of the 22 passengers aboard, 15 were rescued, one body was recovered and six were still missing. Search operations at the site of the sunken yacht were continuing on Tuesday.

Here’s what we know about the passengers.

Mike Lynch and his family

Mr. Lynch, 59, is a British software entrepreneur who had once been described as his country’s Bill Gates. He founded the software firm Autonomy, which analyzed clients’ unorganized data, and turned it into one of the most prominent British technology companies of its time. He became a widely known corporate leader, who advised David Cameron, the British prime minister at the time, and joined the board of the BBC.

In 2011, Mr. Lynch sold Autonomy to Hewlett-Packard for $11 billion, which was far above its market value, earning him hundreds of millions. But HP investors almost immediately soured on the transaction, and the American tech giant quickly fired its chief executive — and then Mr. Lynch.

HP later accused Mr. Lynch of misleading it about the state of Autonomy’s business, setting off a decade-long legal ordeal for the British executive, who denied the accusations. U.S. prosecutors charged him and other executives with fraud, and Autonomy’s chief financial officer was convicted in 2018.

Despite appeals to the British government, Mr. Lynch was extradited to the United States last year and was confined to a townhouse in San Francisco ahead of his criminal trial, which began in March. Facing the possibility of decades in prison if convicted, Mr. Lynch and another colleague were instead acquitted of all charges.

Mr. Lynch’s wife, Angela Bacares, 57, accompanied him on the yacht, and she was rescued on Monday when it sank. She was a consistent presence at his trial in the United States. Records show that she controlled Revtom, the company listed as the owner of the Bayesian.

Hannah Lynch, Mr. Lynch and Ms. Bacares’s 18-year-old daughter, was also on the yacht and was among those who were still missing.

The other guests

Among those unaccounted for is Jonathan Bloomer, 70, chair of Morgan Stanley’s international arm and the chairman of Hiscox, an insurance provider that trades on the London Stock Exchange. His wife, Judy Bloomer, 71, is also listed as missing.

“Our thoughts are with all those affected, in particular the Bloomer family, as we all wait for further news from this terrible situation,” Morgan Stanley said in a statement.

Christopher J. Morvillo, 59, a New York-based partner at the international law firm Clifford Chance, is also among those missing. A former federal prosecutor who comes from a family of prominent lawyers, Mr. Morvillo represented Mr. Lynch during his criminal trial in San Francisco. His wife, Neda, 57, was with him on the yacht and is also among those confirmed as missing.

“We are in shock and deeply saddened by this tragic incident,” a representative of Clifford Chance said in a statement.

Survivors include Charlotte Golunski, a partner at Mr. Lynch’s venture firm, Invoke Capital; Ms. Golunski’s husband, James Emslie, and their 1-year-old daughter Sophie. Also rescued were Ayla Ronald, a lawyer at Clifford Chance, and her partner, Matthew Fletcher.

The crew

The yacht had a crew of 10. The body of the chef, Ricardo Thomas, was recovered from the water, the Sicilian Civil Protection Department said.

Elisabetta Povoledo contributed reporting, and Kitty Bennett and Susan Campbell Beachy contributed research.