Pfalzgraph v. Miley, 2019 Ohio 4920

Plaintiffs George and Marjorie Pfalzgraf sued defendants Jeff Miley (Miley Gas Co.) and Antero Resources, alleging an oil-and-gas lease had terminated for lack of production.
In earlier litigation (2013–2018) the trial court found the lease cancelled for nonproduction; this Court reversed and entered judgment for appellees in July 2018, holding the well produced in paying quantities for the period then at issue.
On December 21, 2018 Pfalzgraf filed a new complaint seeking declaration of lease termination based on alleged nonmaintenance and nonproduction during 2015–2018.
Defendants moved to dismiss under Civ.R. 12(B)(6), arguing res judicata barred the new suit because it arose from the same facts as the prior litigation.
The trial court granted the motion after comparing facts from the prior case to the new complaint; the appellate court reversed, holding the trial court improperly decided res judicata on a 12(B)(6) motion without resort to the complaint alone or conversion to summary judgment.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the trial court properly dismissed the complaint under Civ.R. 12(B)(6) on res judicata grounds	Pfalzgraf: res judicata is an affirmative defense that must be pled under Civ.R. 8(C) and cannot be decided on a 12(B)(6) motion; the new claim concerns a different time period	Miley: the new complaint arises from the same transaction/subject matter as the prior suit, so res judicata bars it and dismissal under 12(B)(6) was appropriate	Reversed: res judicata may not be resolved on a 12(B)(6) motion when resolution requires materials outside the complaint; the trial court improperly compared factual records and should not have dismissed without conversion to summary judgment and notice

Grava v. Parkman Twp., 73 Ohio St.3d 379 (1995) (res judicata bars later actions based on the same transaction or occurrence)
State ex rel. Freeman v. Morris, 62 Ohio St.3d 107 (1991) (res judicata may not be raised by a Civ.R. 12(B) motion)
State ex rel. W. v. McDonnell, 139 Ohio St.3d 115 (2014) (resolution of res judicata often requires materials outside the pleadings)
State ex rel. Hanson v. Guernsey Cty. Bd. of Commrs., 65 Ohio St.3d 545 (1992) (12[B][6] tests sufficiency of the complaint only)
State ex rel. Seikbert v. Wilkinson, 69 Ohio St.3d 489 (1994) (12[B][6] standard: presume complaint allegations true and construe in plaintiff's favor)
Jim's Steakhouse, Inc. v. Cleveland, 81 Ohio St.3d 18 (1998) (affirmative defenses not listed in Civ.R. 12[B] are waived if not pleaded per Civ.R. 8[C])
Ferreri v. The Plain Dealer Publishing Co., 142 Ohio App.3d 629 (2001) (appellate review of a 12[B][6] dismissal is de novo)