In Ear v. Empire Collection Authorities, Inc., 2012 WL 3249514 (N.D.Cal. 2012), Judge Conti addressed the post-Iqbal/Twombly standard required for pleading affirmative defenses under the Rosenthal Act/FDCPA.

It is true that there is a split within this circuit, but judges in this district have, uniformly so far as the undersigned can tell, adopted the plausibility standard. E.g., Barnes v. AT & T Pension Ben. Plan–Nonbargained Program, 718 F.Supp.2d 1167, 1172 (N.D.Cal.2010); Dion, 2012 WL 160221, at *2. The plausibility standard “serve[s] to weed out the boilerplate listing of affirmative defenses which is commonplace in most defendants’ pleadings where many of the defenses alleged are irrelevant to the claims asserted.” Barnes, 718 F.Supp.2d at 1172. In doing so, it furthers the underlying purpose of Rule 12(f), which is to avoid spending time and money litigating spurious issues. See Fantasy, Inc. v. Fogerty, 984 F.2d 1524, 1527 (9th Cir.1993), rev’d on other grounds, 510 U.S. 517 (1994). Just as a plaintiff’s complaint must allege enough supporting facts to nudge a legal claim across the line separating plausibility from mere possibility, Twombly, 550 U.S. at 570, a defendant’s pleading of affirmative defenses must put a plaintiff on notice of the underlying factual bases of a plausible defense, Barnes, 718 F.Supp.2d at 1172–73. Mere labels and conclusions do not suffice. See Twombly, 550 U.S. at 555. The Court emphasizes that this standard is not a high one: A defendant need only “point to the existence of some identifiable fact that if applicable … would make the affirmative defense plausible on its face.” Id. at 1172. Defendants do not need to “establish conclusively in their initial pleading that their affirmative defenses must carry the day.” Dion, 2012 WL 160221, at *3. Moreover, if, at a later stage in the litigation, defendants uncover facts which would permit them to plead an affirmative defense not previously asserted, they need only seek the Court’s leave to amend their answer, assuming no prejudice to other parties will ensue from amendment.