Tengizchevroil is a joint venture between Chevron (50% share in the consortium), ExxonMobil (25% share), KazMunayGas (20% share) and LukArco (5% share). The joint venture was formed in April 1993, when the Kazakhstan government granted an exclusive 40-year right to Tengizchevroil LLP (TCO) to develop the Tengiz and Korolevskoye oil fields located in the north-eastern reaches of the Caspian Sea in Kazakhstan.
From a two-company joint venture in 1993 (between Kazakhstan state oil company KazakhOil, now KazMunayGas, and the USA company Chevron) Tengizchevroil expanded in 1996-1997 into a four-company consortium: ExxonMobil Kazakhstan Ventures, an ExxonMobil subsidiary, and LukArco, a joint venture between Lukoil of Russia and Atlantic Richfield (Arco) of the USA, acquired 25% and 5% respectively. Since 2000 British BP had a part in it as well, since BP merged with Arco and took its 46% share in LukArco. In December 2009, BP sold its stake to Lukoil and thereafter Lukoil became a sole shareholder of LukArco.
In January 2014, the firm reported a record rise in output to 27.1 million tonnes from 24.2 million tonnes.