NK Rosneft� OAO (Oil Company Rosneft OJSC) is a Russia-based company engaged in exploration, development, production and sale of crude oil and gas, as well as refining, transportation and sale of petroleum products. It has three business segments. The exploration and production segment is engaged in field exploration and development, and production of crude oil and natural gas. The refining, marketing and distribution segment is engaged in processing crude oil and other hydrocarbons into petroleum products, as well as the purchase, sale and transportation of oil and oil products. In 2013, it acquired TNK-BP Holding OAO, a 51% stake in Petroresurs LLC, as well as consolidated a 100% stake in Elvary Neftegaz ZAO, NGK Itera OOO and TNK-Sheremetyevo LLC. In September 2013, it acquired a number of oil and gas assets in Yamalo-Nenets Autonomous Region. On October 14, 2013 it consolidated 100% of Taas-Yuriakh Neftegazodobycha LLC into Rosneft's subsidiary, RN-Vostochnaya Sibir LLC.