Eventually, the Roman art of baking became known throughout Europe and eventually spread to eastern parts of Asia. By the 13th century in London, commercial trading, including baking, had many regulations attached. In the case of food, they were designed to create a system "so there was little possibility of false measures, adulterated food or shoddy manufactures." There were by that time twenty regulations applying to bakers alone, including that every baker had to have "the impression of his seal" upon bread.