no pet.). A release that is valid on its face, however, constitutes prima facie proof of payment; the burden of proving otherwise is on the party who denies its validity. Martin v. Farmers’ Nat’l Bank of Hillsboro, 294 S.W. 240, 241 (Tex.Civ.App.-Waco 1927, no writ); see also Deer Creek Ltd. v. N. Am. Mortgage Co., 792 S.W.2d 198, 201 (Tex.App.-Dallas 1990, no writ) (“Once the release was properly pleaded, the burden then shifted to appellants to produce evidence that raised a fact issue as to a legal justification for setting aside the release.”). 2. Analysis Here, McKenna, an agent of the AG, signed and acknowledged the Release, and the AG itself asserted in its motion for new trial that it does not dispute the trial court’s fi S.W.3d 564, 570-71 (Tex.App.-San Antonio 2004, no pet.) (<HOLDING>). Because the Release is valid on its face, and
recognizing section 52112 as an affirmative defense holding that fair use is an affirmative defense recognizing laches as an affirmative defense recognizing lack of consideration as an affirmative defense to a release that is valid on its face holding that laches is an affirmative defense