In 2004, just five years after introducing the drug, Vioxx, pharmaceutical company, Merck, voluntarily withdrew the prescription pain-killer after a clinical study suggested that the drug increased the risk of heart attack and stroke. But in that relatively short time, an estimated 20 million Americans had already taken the drug. By late 2007, Merck announced it would pay $4.85 billion — the largest drug settlement ever — in “global settlements” for Vioxx-related claims. These settlements ultimately included roughly 47,000 individual lawsuits and about 265 potential class actions, but the Vioxx settlements were far from global. In 2012, a purported parallel state court class action proceeded on a collision course with the “global settlement...