2. David Reuben & Simon Reuben
Reuben brothers make fine switch
£3,300m
Global Switch
2008: £3,300m (No change)
The Reubens' main property company, Aldersgate, had £530m written off by the end of November 2008, knocking its value down to £2.4bn. In addition, their Reubros financial investments arm lost £320m, cutting its assets to £2.2bn.
But the brothers have always been able to spot value and make a profit by trading assets. In July 2007 they shared a £150m profit on the £494m sale of Shell Mex House on London's Strand. In the same year, they took full control of fast-growing data-centre business Global Switch. And in May 2009, they were reported to be in talks with an American hedge fund to sell a stake that effectively valued the business at about £1.9bn.
The Reubens, David, 71, and Simon, 68, have been active in British property for the past decade after making their fortune in Russia in the 1990s, where they were dubbed the "metal tsars" for their role in restructuring the aluminium industry there.
Born in Bombay, the Reubens made their way to London, where Simon went into property and David started trading in scrap metal. Their foray into Russia, which ended in 1999, earned them at least £1.3bn.
The success of Global Switch has helped the Reubens to weather the fall in property values. Allowing for debt, we value them at £3.3bn.