Pool & Issue

Pools are formed by grouping similar mortgages—same coupon, maturity, and issuer—into securities that comply with GSE or Ginnie Mae eligibility standards. For Ginnie Mae pools, loans must be fully originated, funded, and backed by FHA, VA, or RHS guarantees. Fannie Mae and Freddie Mac pools undergo additional review under their Single Family Loan Sale programs. Pool composition must meet predefined maximum loan size, LTV, and borrower profile limits before submission to the issuer.

Securitization structures like planned amortization class or targeted amortization class tranches are defined in indentures filed with the SEC under Section 5 of the Securities Act. Trust indentures outline payment priorities, credit enhancements, and distribution mechanics. Subordinate tranches absorb initial losses, while senior tranches receive priority of payment. Issuers appoint a master servicer and special purpose vehicle, often with custodians like U.S. Bank or Citibank, to hold collateral and ensure compliance with pool-level covenants.

Post-issuance, the MBS or CMO undergoes initial pricing and rating by agencies like S&P, Moody’s, or Kroll, based on cash flow modeling and collateral analysis. The offering statement includes detailed information about loan characteristics, geographic diversification, and prepayment assumptions derived from historical benchmarks like HPA or FMG models. Investors rely on these disclosures for due diligence, and the SEC maintains accessibility to filed documents via EDGAR for ongoing transparency.