On August 12, the FHFA requested comments on the structure of a proposed single security that would be issued and guaranteed by Fannie Mae or Freddie Mac (the GSEs). The implementation of the single security would be part of a “multi-year initiative” to build a common securitization platform. The request explains that the proposed single security would generally encompass many of the pooling features of the current Fannie Mae Mortgage Backed Security (MBS) and most of the disclosure framework of the current Freddie Mac Participation Certificate (PC). The single security would have key features that exist in the current market, such as: (i) a payment delay of 55 days; (ii) pooling prefixes; (iii) mortgage coupon pooling requirements; (iv) minimum pool submission amounts; (v) general loan requirements, such as first lien position, good title, and non-delinquent status; (vi) seasoning requirements; and (vii) loan repurchase, substitution, and removal guidelines. The GSEs would continue to maintain their separate Servicing and Selling Guides for the single security. The FHFA is especially interested in comments on how to preserve “to-be-announced” (TBA) eligibility and ensure that legacy MBS and PCs are “fully fungible” with the single security. The FHFA also seeks specific input on: (i) what key factors regarding TBA eligibility status should be considered in the design of and transition to a single security; (ii) what issues should be considered to ensure broad market liquidity for the legacy securities; (iii) what operational, system, policy, or other effects on the industry should be considered; and (iv) what can be done to ensure smooth implementation of a single security with minimal risk of market disruption. Comments are due by October 13, 2014.