Rambler Media Ltd. signed in July an agreement with Google on selling its Begun (Runner) contextual advertising system to the U.S.-based Internet search company for $140 million.
The Anti-Monopoly Service said it had rejected the bid as Google had failed to provide all the information necessary to clarify the financial aspects of the deal.
At the time of the July deal, Rambler owned 50.1% of shares in Begun and intended to repurchase the remaining 49.9% package from the investment company Finam in order to resell the entire 100% stake to Google.
"The documents lack information on persons capable of influencing the economic operations of Google. Also, there is no full list of persons involved in Google - in Russia and abroad," the competition watchdog said.
Begun, a leading Russian contextual advertising seller, works with 143,000 partner web sites across Russia.