(February 17, 2017, 1:25 PM EST) -- CINCINNATI — Parties in a securities class action lawsuit recently asked the Sixth Circuit U.S. Court of Appeals to determine whether a federal district court erred in dismissing the lead plaintiffs’ amended complaint for failure to plead loss causation (Norfolk County Retirement System v. Community Health Systems Inc., et al., No. 16-6059, 6th Cir.)....