Fannie Mae, Freddie Mac and Ginnie Mae have been around for decades and they dominate the residential MBS market, but the agencies are not standing still. Pushed by their federal conservator, Fannie and Freddie are rebuilding their securitization infrastructure and trying to reinvent how they do business with mortgage sellers. At the annual convention of the Mortgage Bankers Association this week, the Federal Housing Finance Agency announced an agreement in principle on changes to the representations-and-warranties framework used by the government-sponsored enterprises. Ginnie officials disclosed new issuer eligibility standards and performance evaluations. “GSE reform does not mean...