Bill Ackman's Pershing Square L.P. hedge fund returned 25% in the first half of the year, according to an investor update, helped by the activist investor's backing of a hostile takeover bid for Botox ...

Don't send out any save-the-dates for that Allergan special shareholder meeting just yet. Valeant has won a request for an expedited trial over the timing of the meeting, a key step in its $50 billion ...

Hedge fund manager Bill Ackman, who runs Pershing Square Capital Management, has a long career of successful investments. However, what Ackman will likely be best remembered for is his gigantic ...

Valeant Pharmaceuticals International is now searching for a new chief executive officer, having told current CEO Mike Pearson over the weekend that he is no longer in the company's long-term plans.