Merck and Schering-Plough shareholders filed a class action lawsuit alleging that Merck, Schering-Plough Corporation and Merck/Schering-Plough Pharmaceuticals violated the federal securities laws by failing to disclose material information and making false and misleading statements about the commercial prospects of the cholesterol drug Vytorin (a combination of the Merck drug Zocor and the Schering-Plough drug Zetia) between 2006 and 2008. They claimed that the defendants concealed the results of a clinical test (known as the “ENHANCE” study) that showed Vytorin was no more effective than Zocor alone. The plaintiffs also alleged that Schering made false and misleading statements in connection with offerings of Schering stock in August 2007. In June 2013, the lawsuit was settled for $473 million. See related Merck instances, “Vytorin/Zetia Securities Litigation” and “Vytorin Multistate Investigation”.