A person that is an MSB solely because that person serves as an agent of another MSB is not required to register. However, a person that is an MSB both because it engages in MSB activities on its own behalf and as an agent of another MSB must register.
Example: A supermarket corporation that acts as an agent (as a seller of money orders) for an issuer of money orders, and performs no other services of a nature and amount that would cause the supermarket corporation to be a money services business, is not required to register. The result is the same if the supermarket corporation serves as an agent for two or more MSBs. Thus, if the supermarket corporation serves as an agent both of a money order issuer and of a money transmitter, it is not required to register. However, registration is required if the supermarket corporation --in addition to acting as an agent of a money order issuer --cashed checks or exchanged currency (other than as an agent for another MSB) in an amount greater than $1,000 for any person on any day in one or more transactions.
31 CFR 1022.380(a)(2) (formerly 103.41(a)(2))