Russia's largest search engine, Yandex (NASDAQ:YNDX), will repurchase up to 12 million Class A shares in a new repurchase program the board of directors authorized following the announcement that certain shareholders, including company founders Arkady Volozh and Ilya Segalovich, plan to sell 24.25 million shares.

The buyback program will be run until at least Nov. 14, and if the company's shareholders renew the board's authority to repurchase shares at the 2013 annual general meeting, the program will be extended until March 2014.

As of March 11, Yandex had outstanding 222 million Class A shares, 107 million Class B shares, and 47 million Class C shares.

There was no pricing disclosed on the secondary offering of 24.25 million Class A shares that was also announced yesterday, though at yesterday's closing price of $25.03 the transaction would be valued at approximately $607 million. Yandex will not receive any of the proceeds from the offering, which is being managed by Morgan Stanley, Deutsche Bank, and Goldman Sachs, which have been granted a 30-day option to purchase an additional 2.43 million shares, or 10% of the offering.