Anyone seeking broker authority must file a Form OP–1 and submit it to FMCSA. Companies with existing motor carrier authority should include their current USDOT Number on the OP–1 form but leave the MC Number field blank. FMCSA will issue a separate MC Number for the broker authority. While MAP–21 requires FMCSA to establish an indicator of the type of transportation or service for which the USDOT registration number is issued, including whether the registration number is issued for registration of a motor carrier, freight forwarder, or broker, FMCSA will implement this provision at a later time. Source: 78 FR 54720, Sept. 5, 2013.