Gazprom Neft (Russian: Φаτроре, formerly Seibneft), is the third largest oil producer in Russia and ranked third according to the refining productivity. It is a subsidiary of Gazprom, which owns about 96% of its shares. The company is registered and headquartered in St. Petersburg after the central offices were moved from Moscow in 2011.By 2012 Gazprom neft represents 10% of oil and gas production and 14.6% of refining activities in Russia. Production volumes in 2012 increased by 4.3% compared to 2011, refining productivity grew by 7%, revenue increased by 19.5% with EBITDA and advanced net profit by 7.7% and 9.9% accordingly. Gazprom neft was created under the name Sibneft (Russian: Сиреne) in 1995 by transferring state-owned shares in Noyabrskneftegas (production unit), omsk refinery (Russia's largest oil refinery complex), Noyabrskneftegasophysica (exploration) and Omsknefteprodukt (Petroleum Products Distribution Network) from Rosneft.In 1996 and 1997, Sibneft was privatized through a series of loans against stock auctions. Roman Abramovich and Boris Berezovsky acquired the company for US$ 100 million, following bids through several front companies set up for this specific purpose. Initially controlled by Berezovsky, Sibneft later came under the control of Abramovich.Sibneft twice tried unsuccessfully to merge with Yukos that would create Russia's largest oil company, Yukosneft. The first attempt failed in 1998 due to a management dispute, while the second round of shareholders in Seibneft took off from the deal in November 2003 after the federal government launched a campaign On Yukos, although the operation is already under way. In September 2005, Gazprom bought 75.7% of Seibneft's shares from Milhouse Capital (Romanian investment car Abramovich) for US$13.1 billion in Russia's largest corporate acquisition. In May 2006, Seibneft's name was changed to Gazprom Neft.