PTT was registered in 2001 following the privatization of the Petroleum Authority of Thailand, the state enterprise. PTT is engaged in the exploration and production of oil and natural gas and the international trading of crude oil, liquefied petroleum gas (LPG) and petrochemical and feedstock. It had an initial registered capital of THB20 billion; the Ministry of Finance is the largest shareholder. It listed on the Thai Stock Exchange in 2001.