This report presents the findings of a Federal Judicial Center study on the filing and resolution of motions to dismiss for failure to state a claim under Rule 12(b)(6) of the Federal Rules of Civil Procedure. The study was requested by the Judicial Conference Advisory Committee on Civil Rules. This request was prompted by two recent Supreme Court decisions — Bell Atlantic Corp. v. Twombly, 550 U.S. 544 (2007), and Ashcroft v. Iqbal, 556 U.S. 662 (2009) — that interpreted Rule 8(a) by stating that a plaintiff must present a "plausible" claim for relief.