Beware of the commercial breeder. Any breeder licensed with USDA or registering their litters through USDA is a commercial breeder. All puppies found in pet shops are from commercial breeders even if they are not registered with USDA. Pet store owners are only permitted to purchase puppies from USDA regulated commercial breeders or brokers.
The American Kennel Club (AKC) does inspect breeders who breed 7 or more litters per year. Many times, but not always, an AKC inspected breeder is also a backyard breeder breeding for profit versus for the betterment of the breed. Seven litters in one year is a lot of litters, so if your breeder is AKC inspected make sure they have the time needed for each individual puppy and are following the Orthopedic Foundation for Animals (OFA) health testing guidelines set forth for their breed.