The Federal Housing Finance Agency this week filed suit against UBS Securities and various related entities as well as former top officials of the firm over alleged misrepresentations on subprime and Alt A MBS sold to Fannie Mae and Freddie Mac. The two government-sponsored enterprises bought some $4.5 billion of non-agency MBS issued on two UBS shelf registrations between September 2005 and August 2007. The deals included single-seller and conduit transactions with mortgages originated by ...