Fannie Mae and Freddie Mac have been content to let their significant holdings of non-agency mortgage-backed securities run off in recent years as opposed to selling the investments at a loss. However, the government-sponsored enterprises will likely have to sell some of their vintage non-agency MBS due to a mandate from the Federal Housing Finance Agency. A set of goals for the GSEs in 2013 released this week by the FHFA includes reducing the GSEs’ retained portfolio balances by selling 5 percent of the assets ...