Dubliner Silvester, 56, runs Enstar, the Bermuda-based insurer founded in 1993 as Castlewood. It merged in 2001 and he is now chief executive of the enlarged Nasdaq-quoted operation, with a stake worth €122m and an annual pay packet of €4.4m. Share sales since 2009 top €160m. He has a €41.2m share of the London-based Secure Income property business founded by Nick Leslau. A past pupil of Blackrock College, Silvester and his wife Julie paid €10m in 2007 for a house in Wellington Road, Dublin, where they are building a three-storey extension. Other assets include a stake in Saracens rugby club. With reinvestments, he is worth €282m.