Allergan sues Valeant, Ackman for alleged insider trading

Botox maker Allergan Inc. on Friday accused rival Valeant Pharmaceuticals International and billionaire investor William Ackman of violating securities laws by using insider information as they prepared a takeover bid for the drug company.

The lawsuit alleges Ackman's Pershing Square Capital Management and Valeant worked together to illicitly conduct an insider-trading scheme allowing the hedge fund to buy Allergan shares, knowing about Valeant's planned $51 billion takeover bid, according to Reuters.

Valeant and Pershing Square have responded by saying the complaint was intended to prevent them from calling a special meeting of Allergan shareholders to vote on board nominees.

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