Fannie Mae & Freddie Mac
Fannie Mae (Federal National Mortgage Association) and Freddie Mac (Federal Home Loan Mortgage Corporation) are government-sponsored enterprises (GSEs) that buy mortgages from lenders, package them into mortgage-backed securities, and sell those securities to investors. This provides liquidity to the mortgage market.
They set the conforming loan rules: loan size limits, credit standards, documentation requirements. Most U.S. mortgages are originated to fit these rules and then sold to Fannie or Freddie. Loans that don't fit (jumbo, non-QM, foreign national) stay on the originator's balance sheet or sell to private investors.
Why it matters for Milo customers
Milo is a portfolio lender — Milo's crypto-backed mortgages don't conform to Fannie/Freddie standards (the GSEs don't yet underwrite on crypto collateral), so Milo holds them on its own balance sheet. This is why Milo can offer products the agency lenders can't.