Five major banks and four traders were sued on Wednesday in a private U.S. lawsuit claiming they conspired to rig prices worldwide in a more than $9 trillion market for bonds issued by government-linked organizations and agencies. Bank of America Corp (BAC.N), Credit Agricole SA (CAGR.PA), Credit Suisse Group AG (CSGN.S), Deutsche Bank AG (DBKGn.DE) and Nomura Holdings Inc (8604.T) were accused of secretly agreeing to widen the "bid-ask" spreads they quoted customers of supranational, sub-sovereign and agency (SSA) bonds. The lawsuit filed in Manhattan federal court by the Boston Retirement System said the collusion dates to at least 2005,...