Entrepreneur Mike Lynch and his 18-years-old daughter, Hannah, are two of the four Brits missing hours after the £14m luxury vessel Bayesian capsized after a tornado hit the yacht.
Two others are also feared dead after the boat sank off the coast of the Italian island.
Lynch's family, lawyers, and employees were on the boat when it sank as they were celebrating his victory over fraud charges that ended him up him 25 years in prison.
Lynch’s wife, Angela Bacares, is among those who have been rescued.