If Goodyear was prey to leverage, Allergan appears a victim of tax arbitrage. In fact, the tax situation could become a hot political issue—Allergan is hardly an isolated case. Two drug industry giants, Pfizer Inc. and Walgreen's, also are considering foreign mergers in order to escape the U.S. tax rate. The Allergan battle might also be a test of Wall Street, pitting "value" investors against hedge funds and others with short-term horizons. It's one thing to flog Goodyear for becoming bloated. It's another to savage Allergan for trying to ensure long-term profitability through R&D. Indeed, a number of Allergan's institutional investors have expressed concerns that Valeant stock they'd receive in a takeover could depreciate. Dan Davidowitz, chief investment officer of Polen Capital Management, told the Wall Street Journal that he thought Allergan could match the Valeant price "just from another couple of years of compound earnings growth. So I don't think this is that attractive an offer."