Mr. Berezovsky may have committed suicide. A lawsuit, in which Mr. Berezovsky had brought a $5.1 billion claim against Roman A. Abramovich in a dispute over the sale of shares in the Russian oil company Sibneft and other assets, ended in a spectacular defeat. Recent news reports described how Mr. Berezovsky had begun to sell personal assets, including a yacht and a painting by Warhol, “Red Lenin,” to pay debts related to the lawsuit. Mr. Berezovsky was a leading Soviet mathematician who after the fall of Communism went into business and figured out how to skim profits off what was then Russian’s largest state-owned carmaker. Along with spectacular wealth, he accumulated enormous political influence, becoming a close ally of Mr. Yeltsin’s. With Mr. Yeltsin political career fading, Mr. Berezovsky helped engineer the rise of Mr. Putin, an obscure former K.G.B. agent and one-time aide to the mayor of St. Petersburg, who became president of Russia in 2000 and last May returned to the presidency for a third term. After his election, Mr. Putin began a campaign of tax claims against a group of rich and powerful Russians, including Mr. Berezovsky and the oil tycoon Mikhail B. Khodorkovsky, who remains jailed in Russia. Mr. Berezovsky fled to London, where he eventually won political asylum and at one point raised tensions by calling for a coup against Mr. Putin. ****************************************************** In 2000 the family fled from Russia. They first lived in France, before moving to the United Kingdom in 2001. The family moved to a property known as Wentworth Park in Surrey, which was chosen and furnished by Ms Gorbunova. In 2003 Mr Berezovsky was able to obtain political asylum, and he changed his name to Platon Elenin*. The threats against the couple continued during their time in the UK, and the reality of these threats was brought home by the murder of Alexander Litvinenko in 2006. ********************************************************** A few months after the election Mr Berezovsky fled Russia, and applied successfully for asylum in the UK after Mr Litvinenko, an officer with the KGB's successor, the FSB, came forward to say he had been ordered to murder the tycoon. Mr Berezovsky changed his name to *Platon Elenin*, Platon being the name of a character in a Russian film based loosely upon his life. He was subsequently given a British passport in this name.