Low-key and media-shy Andy Ruhan (53), who grew up in Athenry, Co Galway, has amassed a fortune thanks to success in a data centre business, hotel and properties and a cable firm.
Sentrum, a data centre venture, sold a three-property portfolio to Digital Realty for 850m in 2012. Then in a highly-leveraged deal, Ruhan made money from flipping the Thistle chain of 32 hotels and converted many of them into high-end apartments. It has emerged that a deal involving two of the London hotels alone, which involved the Candy Brothers, saw the site flipped within just 18 months to a Middle East buyer for a cool £250m profit in 2008.
It has also emerged that he and his brother Gabriel made money from the sale of Global Marine Systems, an undersea cable firm, for 200m in 2014. When IT services firm Navisite was sold to Time Warner, it earned them about 127m, so we've upped his net worth considerably from last year's figure.
Among the other assets owned by Andy are a hotel in Wimbledon, a multi-million pound mansion in Buckinghamshire and an African game reserve. He is also an avid motor racing fan and sat on the board of the Lotus F1 team
before Renault took it over at the end of 2015. A classic car collection includes a rare 1962 E-type Jaguar.