The DOC has legal status in Italy - anything else is NOT pizza.
The rules for pizza under the DOC are:
1) Pizza dough must be made with flour, water, yeast and salt only. No additives such as oil, fat, sugar or milk are allowed.
2) Pizza must be no greater than 30 cm. (12 inches)
3) Dough should not be heated by the mixing process. (slow electrical mixers or hand mixing only)
4) Dough must be hand stretched, no rollers or presses.
5) The oven must be made of refractory material such as brick or castable refractory and fired with wood.
6) The pizza must be cooked on the floor of the oven. (no pans)
7) Pizza must be cooked at 400 deg. C. or higher. (750 deg. F)
8) Pizza should be well done, fragrant, with the cornicione (border) high and soft. Pizza should not be crusty.