Welcome to YorkieTalk
Small Yorkies sure are cute but there is really no such thing as a teacup. A Yorkie is a Yorkie. The American Kennel Club says that any Yorkie that is 7 pounds or below is within standard. If they are over 7 pounds, they are still Yorkies, just not standard. Some breeders who are only in it for the money will use the words teacup, mini, or micro for their own gain. Some Yorkies only get to be about 2 pounds which is fine, it is not good when the breeder is breeding for small size. The smaller the Yorkie is, the more potential for injury.