Municipal Securities Rulemaking Board

The Municipal Securities Rulemaking Board (MSRB) is a United States self-regulatory financial organization that writes investor protection rules and other rules regulating broker-dealers and banks in the municipal securities market. This including tax-exempt and taxable municipal bonds, municipal notes, and other securities issued by states, cities, and counties or their agencies to help finance public projects or for other public policy purposes.

Source: Wikipedia — Municipal Securities Rulemaking Board (CC BY-SA 4.0)