"[T]he U.S. Court of Appeals for the Sixth Circuit held that a 401(k) plan participant who sued under the Employee Retirement Income Security Act (ERISA) for losses in connection with a company stock fund that suffered a drop must show losses on a net basis during the class period to have constitutional standing. This decision has great significance in addressing plaintiffs' standing and class certification in so-called ERISA 'stock-drop' cases, often filed after a company's stock price falls."