Wells Fargo analyst David Maris believes the selloff today in shares of Allergan (AGN) on news the company is considering a bid for Shire (SHPG) is understandable. Many believe Allergan was in the process of trimming, not bulking up, Maris tells investors in a research note. He believes that if CNBC's subsequent report is true and Allergan won't be making a bid, the "about-face would be an incredible turn given Allergan's press release came out just a couple hours earlier." Further, the analyst thinks investors are now left wondering what type of disruption another major integration could mean for a company that has already had significant organizational change. Maris has an Outperform rating on Allergan with a $245 price target. The stock in afternoon trading is down 4% to $159.36.