Reuters is reporting that billionaire hedge fund manager John Paulson has bought 6 million shares of Allergan, or about a 2% stake.
They're also reporting that Paulson supports an Allergan/Valeant deal.
Paulson, who is a closely-followed fund manager, could be a big ally for Bill Ackman.
Back in April, Ackman, the activist investor who runs $12 billion Pershing Square Capital Management, teamed up with Valeant Pharmaceuticals to pursue a hostile takeover of Allergan, the maker of Botox.
So far, Allergan has rejected Pershing Square's/Valeant's cash-and-stock bids for the company.
Following the Paulson news, shares of of Valeant were last trading up about 4.5% and shares of Allergan were last up about 3%.
Pershing Square owns 28,878,538 shares of Allergan, or about a 10% stake in the company.
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