48-Hour Rule Definition
What Is the 48-Hour Rule? The 48-hour rule is a requirement that sellers of to-be-announced (TBA) mortgage-backed securities (MBS) communicate all pool information regarding the MBS to buyers before 3 p.m. Eastern Time, 48 hours before the settlement date of the trade. The Securities Industry and Financial Markets Association (SIFMA) enforces this rule. SIFMA was formerly known as the Public