Libor scandal: Fannie Mae and Freddie Mac could have lost $3bn "Our customers have significant concerns about the costs to their businesses from banks" manipulating Libor. The bottom line is that we are in various stages of bringing actions against banks for fixing Libor. With much of the world's debt markets based on the interbank lending rate, Libor, the scale of claims facing banks is hard to quantify. A recent research note by Japanese bank Nomura estimated that claims relating just to interest rate swap mis-selling, one product among a range that could be subject to claims, could top $6bn (£3.7bn). A number of claims, including one by care home provide Guardian Care Homes, have already hit the UK courts. Carmen Leon, solicitor at lawyers Rohrer and Co said: "The fact that the FSA has concluded that UBS has colluded with other banks, with nearly a dozen other major mayor banks under investigation, means that this scandal is likely to have affected a large number of businesses in the UK." The manipulation of Libor, together with the sale of interest swaps, could have led to bumper pay outs for banks. Swaps would have pinned company's interest rate payouts to set levels, meaning that when rates fell - sometime as a result of market manipulation - banks" margins would have increased. Ms Leon said: "Today's news about UBS" $1.5bn settlement with UK, US and Swiss authorities has wide ranging implications for businesses whose lending is based on LIBOR and particularly those who were obliged to enter into derivative contracts such as interest rate swaps. The end result of many of these products was that the customer ended up paying significantly more as rates fell.