IRVING, Calif.— Allergan Inc. ((NYSE: AGN), which is continuing its efforts to fend off an unsolicited, $54 billion takeover bid by Valeant Pharmaceuticals International (NYSE: VRX), the parent company of Bausch + Lomb Inc., asked a judge to block Bill Ackman’s Pershing Square from voting at a shareholder meeting scheduled for December.

According to several published news reports at VMail presstime, Allergan filed its request on Monday night in federal court in California, where it is litigating claims that Ackman engaged in insider trading by acquiring a 10 percent stake in the company based on non-public knowledge of Valeant Pharmaceuticals International Inc. plans to bid for Allergen. A hearing on the request is scheduled for Oct. 28.

Pershing Square is Allergan’s largest shareholder and has sought a Dec. 18 meeting to replace six board members, clearing the way for Allergan to accept Valeant’s takeover bid, as VMail has previously reported. The current board said as recently as Sept. 29 that Valeant’s offer is “grossly inadequate.”

In its lawsuit, Allergan seeks to have Pershing Square’s acquisition of its shares voided based on the allegations of insider information. Allergan alleges that Pershing Square, starting in February, acquired $3.2 billion of its shares because it was informed Valeant would make a bid.

At presstime, Allergan and Valeant had not posted additional comment or an official response to the filing.