Yes. In the US you must follow US Drug Enforcement Administration rules for buying and selling. It is a federal offense to sell certain proscribed chemicals to a buyer unless he or she has submitted the DEA purchasing forms. You must also abide by all shipping regulations. Many chemicals cannot be shipped by United States Postal Service. If you do, you can get into a world of legal trouble with the US Federal Government. You have to do a lot of homework to learn how to do so legally.