William Knox D'Arcy was a British-Australian businessman who was one of the principal founders of the oil and petrochemical industry in Persia (Iran). The D’Arcy Concession was signed in 1901 and allowed D'Arcy to explore, obtain, and market oil, natural gas, asphalt, and ozokerite in Persia.

The D'Arcy Concession was a petroleum oil concession that was signed in 1901 between William Knox D'Arcy and Mozzafar al-Din, Shah of Persia. The oil concession gave D'Arcy the exclusive rights to prospect for oil in Persia. During this exploration for oil, D'Arcy and his team encountered financial troubles and struggled to find sellable amounts of oil. Facing high costs, they were about to give up but eventually struck large commercial quantities of oil in 1908. The Burmah Oil Company created the Anglo-Persian Oil Company to take over the concession in 1909.