Air Liquide S.A. (French pronunciation: ​[ɛʁ likid]; /ˌɛər lɪˈkiːd/; literally "liquid air"), is a French multinational company which supplies industrial gases and services to various industries including medical, chemical and electronic manufacturers. Founded in 1902, after Linde it is the second largest supplier of industrial gases by revenues and has operations in over 80 countries. It has headquarters at the 7th arrondissement of Paris. Air Liquide owned the patent for Aqua-Lung until it expired.