Committee on Uniform SecuritiesSecuritiesMBS, PFP MBS, or REMIC. Identification Procedures 9-digit security identification number assigned by Fannie MaeFannie MaeThis Glossary term Is Created Using Automation in Lower Environments and is used for testing purposes only!! to identify the MBS PoolMBS PoolMBS Security backed by MBS Mortgage Loans. in the book-entry system.