The last assets of Russia's bankrupt oil company Yukos, including its HQ, have been sold to little-known firm Paran for 100bn roubles ($3.9bn; £2bn).
The sale price of the headquarters exceeded expectations
The company outbid state-run Rosneft - the expected winner - by offering four times the opening bid.
The move marks the end of once-dominant Yukos, whose assets are being sold to pay off $26bn in tax bills imposed after fraud investigations.
On Thursday, an offshoot of Rosneft bought Yukos' last production assets.
Rosneft bought the last outstanding refining and production asset of Yukos - Samaraneftegaz - at auction for 165.5bn roubles.
The starting price at Friday's auction which included the 22-storey Moscow headquarters, as well as various subsidiary outfits, had been 22bn roubles.
It had been widely thought Rosneft - which has been buying up Yukos assets for several years - would buy the headquarters.
By buying Yukos assets including its three main production units -Yuganskneftegaz, Tomskneft and Samaraneftegaz - Rosneft now owns more than 40% of Russia's oil production.
Thursday also saw 537 Yukos petrol stations sold at an auction, to energy firm Yuniteks.
As well as facing huge debts, Yukos former chief executive and founder Mikhail Khodorkovsky was jailed for tax evasion.
Yukos has argued that the tax demands made by the government were tied to a political campaign against Mr Khodorkovsky, who is currently serving an eight-year prison sentence in Siberia.
Russia's government started breaking up Yukos in 2003 after Mr Khodorkovsky was sent to prison.