From 2005 to 2007, Fannie and Freddie bought approximately $1 trillion in sub-prime and Alt-A loans. This amounted to about 40 percent of their mortgage purchases during that period. Moreover, Freddie purchased an ever-increasing percentage of Alt-A and sub-prime loans for each year between 2004 and 2007.
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Fannie Mae underwriting guidelines are guidelines that state which mortgages are acceptable for packaging by lenders in preparation for sale to Fannie Mae. It is a common practice among lenders to package bundles of mortgage loans and sell them to companies like Fannie Mae while still retaining the servicing of the loans.Fannie Mae purchases bundles of conforming loans from lenders. Conforming is a word used to describe loans that follow the Fannie Mae underwriting guidelines.
Fannie Mae's guidelines were set by OFHEO.