Four borrowers from Alabama with adjustable-rate mortgages filed a class-action lawsuit this month against 12 banks that establish the London Interbank Offered Rate. The lawsuit suggests that more than 10,000 borrowers meet the class specifications, which cover loans originated from 2000 through 2009, and that the banks made millions of dollars or even billions due to alleged collusion. “This matter arises from a global conspiracy to fix or set LIBOR – the reference point for setting interest rates on ARMs and other loans – by a cabal of prominent financial institutions,” according to the lawsuit filed in the U.S. District Court for the Southern District of New York. The lawsuit is believed to be the first from borrowers regarding LIBOR manipulation. The plaintiffs claim...