Allergan, the Botox maker which is trying to fend off an unsolicited $54 billion takeover bid by Valeant Pharmaceuticals, has asked a judge to block Bill Ackman’s Pershing Square from voting its 10 percent stake at the shareholder meeting scheduled for December. Pershing Square is Allergan’s largest shareholder. Allergan filed its request overnight in federal court in California, where it is charging claims Ackman engaged in insider trading by acquiring his shares based on non-public knowledge of Valeant’s plans to bid for Allergan. Ackman says the lawsuit is without merit. A hearing on the request is scheduled for October 28th.