The 2009 Russia–Ukraine gas dispute was a pricing dispute between Russia and Ukraine that occurred when Russian natural gas company Gazprom refused to conclude a supply contract for 2009 unless Ukrainian gas company Naftogaz paid its accumulating debts for previous gas supplies.
 The dispute began in 2008 with a series of failed negotiations, and on January 1 Russia cut off gas supplies to Ukraine.
 On January 7 the dispute turned to crisis when all Russian gas flows through Ukraine were halted for 13 days, completely cutting off supplies to Southeastern Europe, most of which depends on Russian gas, and partially to other European countries.
The Russia–Ukraine gas disputes refer to a number of disputes between Ukrainian oil and gas company Naftohaz Ukrayiny and Russian gas supplier Gazprom over natural gas supplies, prices, and debts.
 These disputes have grown beyond simple business disputes into transnational political issues—involving political leaders from several countries—that threaten natural gas supplies in numerous European countries dependent on natural gas imports from Russian suppliers, which are transported through Ukraine.
 Russia provides approximately a quarter of the natural gas consumed in the European Union; approximately 80% of those exports travel through pipelines across Ukrainian soil prior to arriving in the EU.
OJSC "Yukos Oil Company" (Russian: ОАО Нефтяна́я Компа́ния Ю́КОС , ] ) was an oil and gas company based in Moscow, Russia.
 Yukos was acquired from the Russian government by Russian oligarch Mikhail Khodorkovsky's Bank Menatep during the controversial "loans for shares" auctions of the mid 1990s.
 Between 1996 and 2003 Yukos became one of the biggest and most successful Russian companies, producing 20% of Russia's oil output, as much as Libya or Iraq, and Khodorkovsky became an advocate of democratization, international co-operation and Russian reform.
 In October 2003 Khodorkovsky—by then the richest man in Russia and 16th richest man in the world—was arrested, and the company was forcibly broken up for alleged unpaid taxes shortly after and declared bankrupt in August 2006.
 Courts in several countries later ruled that the real intent was to destroy Yukos and obtain its assets for the government, and act politically against Khodorkovsky.
 In 2014 the largest arbitration award in history, $50 billion (€37,2 billion), was won by Yukos' former owners against Russia.
Chornomornaftogaz (also: Chernomorneftegaz, Ukrainian: Чорноморнафтогаз , Russian: Черноморнефтегаз , lit.
 "Black Sea oil and gas") is an oil and gas company located along Krymgazseti in Simferopol, Crimea.
 It is legally a subsidiary of Ukraine's state-owned oil and gas company Naftogaz.
 However, after the 2014 Crimean crisis it was seized by the region's parliament in the run-up to its annexation by Russia.
 There was also a privately owned oil company Chernomorneftegaz, registered in Moscow in 1998 and purchased by Rosneft in 2011, which is not linked to Chornomornaftogaz.
ITERA International Group of Companies controlled by Russian businessman Igor Makarov headquartered in Moscow, Russia, with parent companies of the group registered in Cyprus (In 2015 ITERA International Group of Companies was transferred to ARETI International Group as a result of rebranding).
 Its subsidiaries are involved in the energy industry, civil and industrial engineering, and finance and insurance.
 The company operates primarily in Russia, the Commonwealth of Independent States (CIS) countries and Latvia.
 In 2013, its main subsidiary Itera Oil & Gas Company—was acquired by Russian state-controlled oil company Rosneft.
Badr Jafar (Arabic: بدر حميد جعفر‎ ‎ ) is an Emirati businessman.
 He is the Chief Executive Officer of Crescent Enterprises, a multinational business.
 He is also the President of its sister company Crescent Petroleum, a privately owned oil and gas company headquartered in the United Arab Emirates.
 Jafar is Chairman of Pearl Petroleum, a five-member international consortium for the development of natural gas assets in the Kurdistan Region of Iraq, and Chair of the Executive Board of Gulftainer, a global ports company.
TECO Energy Inc. is an energy-related holding company based in Tampa, Florida, providing electricity to the greater Tampa area and central Florida, and natural gas throughout the state of Florida through its subsidiaries Tampa Electric Company and Peoples Gas Company respectively.
 Another subsidiary, TECO Services, Inc., provides IT, HR, legal, facilities, and other common services to Tampa Electric, Peoples Gas, and former TECO subsidiary New Mexico Gas Company.
 On September 4, 2015, Emera, a utility holding company based in Halifax, Nova Scotia, Canada, announced the pending acquisition of TECO Energy.
 That purchase closed on July 1, 2016, and TECO Energy, Inc. is now a wholly owned subsidiary of Emera, Inc.
Charles Schusterman (1935–2000) was a Russian-born American businessman and philanthropist.
 He was the founder of the Samson Investment Company, a privately owned oil and gas company with oilfield investments in the United States, Canada, Venezuela and Russia.
 He was a large donor to Jewish causes in the United States and Israel.
 He and his wife, Lynn Schusterman founded the Charles and Lynn Schusterman Family Foundation.
Mikhail Borisovich Khodorkovsky (Russian: Михаи́л Бори́сович Ходорко́вский , ] ; born 26 June 1963) is an exiled Russian businessman, philanthropist and former oligarch, now resident in Switzerland.
KeySpan Corporation, now part of National Grid USA, was the fifth largest distributor of natural gas in the United States.
 KeySpan was formed in 1998 as a result of the merger of Brooklyn Union Gas Company (founded 1895 by merging several smaller companies) and Long Island Lighting Company (LILCO), and briefly operated under the name MarketSpan following the merger.
 On November 8, 2000, KeySpan acquired Eastern Enterprises, Eastern's natural gas distribution subsidiaries including Boston Gas Company, Colonial Gas Company and Essex Gas Company; Eastern's unregulated businesses including ServicEdge Partners, the largest unregulated provider of residential HVAC equipment installation and services in Massachusetts; and EnergyNorth Natural Gas in New Hampshire.
 It also was the operator of the Long Island Power Authority's electrical grid.
 KeySpan had its headquarters in Brooklyn, New York, USA and employed 9,700 people.

Question: Which exhiled Russian businessman acquired a Russian owned oil and gas company based in Moscow, Russia?
Answer: Mikhail Borisovich Khodorkovsky