The BOC-3 (Designation of Process Agents) is a form filed to the FMCSA (Federal Motor Carrier Safety Administration) that designates a process agent in every state in the United States.  The agents are in place to accept any service of notice by that state's Secretary of State or services of process issued by any court in that state. 
 
All FMCSA  motor carriers, brokers, and freight forwarders are required to have a BOC-3 on file with the FMCSA in order to get your authority granted.  A BOC-3 is also required in order to reinstate an MC or FF number that has been revoked.