Pfizer, Allergan Shares Pop After Buyout Rumor By: Benzinga via Benzinga October 13, 2015 at 11:59 AM EDT Two of the world's biggest pharmaceutical giants -- Allergan PLC (NYSE: AGN) and Pfizer Inc. (NYSE: PFE) -- are trending after a ... Read More >> Related Stocks: Allergan Plc Pfizer Teva Pharmaceutical Industries ADR