* Settlement reached after years of litigations
* Claims against Rosneft amounted to up to $4 bln
* The $50 bln of Yukos claim against Russia stands (Adds detail)
MOSCOW, April 1 (Reuters) - Former shareholders of defunct Russian oil firm Yukos have settled all litigation between the company and state-owned oil producer Rosneft in all jurisdictions, the shareholders and Rosneft said on Wednesday.
Most of Yukos' assets were acquired by Rosneft after Yukos was declared bankrupt and its founder Mikhail Khodorkovsky was imprisoned for tax evasion and fraud after he fell foul of the Kremlin. The claims have been in the courts since 2007.
The Yukos case rattled foreign investors and underlined Russian President Vladimir Putin's determination to consolidate power when he arrived into the Kremlin.
Yukos shareholders had filed several lawsuits against Rosneft, claiming damages of up to $4 billion.
Some of the claims, in the name of about 55,000 shareholders, have already been won in court and are unaffected by the agreement announced on Wednesday.
Rosneft's shares were up 3.5 percent in afternoon trade, reaching a four-weak high and outperforming a 1.8 percent rise in the broader Moscow stock market.
Yukos confirmed that it was not a financial settlement. It provides certainty of ownership of important structures and assets for the Dutch entities run by the former Yukos management, it added.
A representative for ex-Yukos shareholders, Claire Davidson, said in a statement: "The terms of the settlement are confidential. Yukos can confirm that the settlement applies to all jurisdictions. The settlement between Yukos and Rosneft has immediate effect."
She added that a ruling last year by an international arbitration court that Russia must pay $50 billion for expropriating the assets of Yukos was unaffected by the settlement, as was an 1.8-billion-euro ($1.94-billion) judgment against Russia by the European Court of Human Rights.
Explaining the decision to settle the litigation, Davidson said the shareholders considered the possibility of lengthy legal processes, legal fees and the uncertainty of the success of the claims and securing payment from the defendant.
Rosneft said the parties had completed a deal and signed all the necessary documents regarding the recall of all legal arguments being carried on in Netherlands, England, Russia, the U.S. and other jurisdictions.
It said a settlement was reached, among others, with Bruce Misamore, former chief financial officer for Yukos, and chief executive officer Steven Theede.
($1 = 0.9282 euros) (Reporting by Vladimir Soldatkin; Editing by Timothy Heritage and Tom Heneghan)