Single Security and Common Securitization Platform (CSP)

The Single Security is a joint initiative between Fannie Mae and Freddie Mac (the Enterprises), under the direction of FHFA, to develop a single mortgage-backed security that will be issued by the Enterprises to finance fixed-rate mortgage loans backed by one- to four-unit single-family properties. The Enterprises will align key components of Fannie Mae’s mortgage-backed securities (MBS) and Freddie Mac's participation certificates (PCs). The goal is to bring additional liquidity and fungibility to the “To-Be-Announced” (TBA) market and to reduce or eliminate the trading disparities that exist today between the Enterprises’ TBA securities. The components of the Single Security initiative include aligning (1) key features, which will mainly follow Fannie Mae’s MBS structure; (2) investor disclosures, which will generally follow Freddie Mac’s PCs; and (3) certain policies and practices related to the removal of loans from securities. In addition, the Single Security effort will allow investors to exchange their legacy 45-day Freddie Mac Participation Certificates (PCs) for new 55-day Single Securities issued by Freddie Mac.

The CSP is a technology and operational platform that is being developed by Common Securitization Solutions, LLC, a joint venture of Fannie Mae and Freddie Mac. CSP will perform many of the core back office operations for the Single Security, as well as most of the Enterprises' current securitization functions for single-family mortgages, on behalf of the Enterprises. The CSP is necessary for the implementation of the Single Security.

Visit the Single Security and Common Securitization Platform Section of the FHFA site for the latest updates on the CSP including whitepapers, progress reports, and other documentation.

Single Security Market Playbook 
Lender/Seller/Servicer and Investor Discussion Presentation 
Single Security Infographic 
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