Jailed Russian tycoon Mikhail Khodorkovsky has passed control over his shares in oil firm Yukos to associates abroad, according to Sunday newspaper reports.
The Sunday Times reported that the voting rights to Mr Khodorkovsky's shares had been transferred under an arrangement put in place prior to his arrest on suspicion of tax evasion and fraud last week.
The newspaper named UK-based Lord Jacob Rothschild of the Rothschild banking dynasty as the recipient of the voting rights.
Lord Rothschild and Mr Khodorkovsky are reported to have formed close ties through their mutual support of charities and arts foundations.
A separate report in the Business newspaper stated that Mr Khodorkovsky's voting rights had been transferred to Leonid Nevzlin, a Russian businessman now resident in Israel.
The Russian authorities last week froze a 44% stake in Yukos, thought to include Mr Khodorkovsky's holdings, making it impossible for the shares to be sold.
But their owners are still entitled to vote on issues affecting the company, and to receive dividend payments.
The rights transfer would make it more difficult for the Russian authorities to take control of the company.
It is widely believed that the case against Mr Khodorkovsky, who made his fortune through controversial privatisation deals in the 1990s, is politically motivated.
He has funded opposition groups, breaking what analysts say was a tacit agreement to stay out of politics in return for avoiding investigation of his financial affairs.
Mr Khodorkovsky's arrest has hit international investor's confidence in Russia, triggering a slump on the Russian stock market last week.