The United States Department of Agriculture (USDA) licenses and inspects wholesale dog breeders and brokers, as well as those that make it part of their business to transport puppies in the wholesale market.
Pet store puppies usually originate at USDA puppy farms where the pups will be booked with a broker shortly after their birth. The breeder calls the broker and tells them what breed, color and size of puppies they have. The puppies are then sold to brokers (middle men) when they are 8 weeks old. Broker vans, cars, trucks and SUVs book an appointment with the breeders, usually meeting them in one centralized location in their area, such as a truck port alongside the interstate. The broker vehicle then moves on to the next stop, usually another truck port 20 miles or so down the road. The broker vehicle spends the day picking up puppies, and then transport them to the broker's facility.