UPDATE 1-Polish tycoon Solorz-Zak buys 10% stake in Bioton

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By Marcin Goclowski

WARSAW, May 20 (Reuters) - Polaris Finance, an investment vehicle of Polish media tycoon Zygmunt Solorz-Zak, has bought a 10 percent stake in Polish biopharmaceutical company Bioton BOTN.WA, Bioton and Solorz-Zak said on Tuesday.

"We bought the shares at market price. It's not a short-term investment; we want to hold Bioton for a minimum of two years," Solorz-Zak told Reuters in a brief phone interview. "In a few months we'll consider (whether to increase our stake)."

In a separate statement, Bioton said Prokom Investments, an investment vehicle controlled by another Polish tycoon Ryszard Krauze, had sold a 3.9 percent stake in the company at 0.63 zlotys per share.

The transaction leaves Prokom Investments with a 33.3 percent stake in Bioton, the company added.

Solorz-Zak, one of Poland's richest men, sold a quarter in pay-TV platform Cyfrowy Polsat CPSM.WA through an initial public offering on the Warsaw bourse earlier this month.

"After the successful debut of Cyfrowy Polsat we were looking for a good, new investment," Solorz-Zak said. "We chose Bioton from among many interesting investments, especially because of its recent share price fall."

He added Bioton had lots of potential and that this was a good time to buy.

Bioton shares closed down 1.6 percent at 0.63 zlotys on Tuesday. They have fallen 28 percent this year. (Writing by Marynia Kruk, editing by Will Waterman)