Ireland-based Horizon Pharma said it offered to buy Depomed for about $3 billion, taking its bid hostile after the smaller drugmaker refused to start talks and rejected the proposal first made in May.
Horizon Pharma's offer of $29.25 per Depomed share is unchanged from the price it offered on May 27 and represents a 42 percent premium to the stock's closing price on Monday.
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Horizon Pharma shares rose 2.8 percent to $35.75 before the bell on Tuesday. Trading in Depomed shares were halted.