The sale was made to pay Yukos' US$ 27.5 billion tax bill, Yuganskneftegaz was originally sold for US$9.4 billion to a little known company Baikalfinansgroup which was later bought by the Russian state-owned oil company Rosneft.
Rosneft later sold Yuganskneftegaz
Based on the context we don't know if they did or did not sell
( z1 sell :ARG0 ( z2 company :name ( z3 name :op "Rosneft" ) ) :ARG1 ( z4 company :name ( z5 name :op "Yuganskneftegaz" ) ) :time ( z6 after ) )