The Case for Application of Comment k to Manufacturing Defect Claims


The Legal Intelligencer

May 27, 2021

By: Stephen J. Finley, Jr.Jonathan T. Woy

Pennsylvania products liability law recognizes strict liability and negligence claims for design defect, manufacturing defect and failure to warn. However, Comment k to Section 402A of the Restatement (Second) of Torts precludes all strict liability claims arising from injuries caused by certain categories of products, including prescription pharmaceuticals and medical devices. This widely adopted rule leaves drug and device manufacturers subject to negligence claims only. The balance struck by Comment k ensures the availability of critical, life-saving therapies by eliminating liability for unavoidable harms.

Pennsylvania’s Unqualified Application of Comment k

Establishing its premise, Comment k begins by acknowledging that certain products “are quite incapable of being made safe for their intended and ordinary use. These are especially common in the field of drugs.” Comment k then instructs that, “the seller of such products, again with the qualification that they are properly prepared and marketed, and proper warning is given … is not to be held to strict liability.” The rationale for applying Comment k to bar non-negligence claims is that certain products are important and desirable, even though they cannot be made entirely safe.

Pennsylvania has long applied Comment k to immunize pharmaceutical and medical device manufacturers from all strict liability claims. The Pennsylvania Supreme Court has adopted Comment k and applied its claim-constraining principles without limitation to all strict liability claims against prescription drug manufacturers. See Hahn v. Richter, 673 A.2d 888 (Pa. 1996). Mindful of this clear dictate from the Pennsylvania Supreme Court, the Pennsylvania Superior Court built upon the Supreme Court’s holding in Hahn and held that Comment k applies equally to preclude strict liability claims against medical device manufacturers. See Creazzo v. Medtronic, 903 A.2d 24 (Pa. Super. Ct. 2006). Pennsylvania’s federal courts generally apply Pennsylvania’s “blanket approach” to Comment k to dismiss all strict liability claims against pharmaceutical and medical device manufacturers. See, e.g., Kline v. Pfizer, No. 08-cv-3238, (E.D. Pa., Oct. 31, 2008) (dismissing strict liability, breach of warranty, and fraud claims against drug manufacturers because “they did not rest on a theory of negligence”).

Despite this categorical bar, a number of trial courts in Pennsylvania have held that Comment k is not applicable to strict liability manufacturing defect claims. This artificial distinction between manufacturing defect claims and other strict liability theories against medical device and pharmaceutical manufacturers runs contrary to Pennsylvania law, is at odds with the terms of Comment k, and undercuts the clear balance of competing policy considerations struck by the drafters of the restatement in determining that imposing strict liability is not appropriate for certain products. The willingness to disregard Pennsylvania’s appellate precedent mandating the broad application of Comment k to manufacturing defect claims has unnecessarily injected uncertainty into pharmaceutical and medical device litigation, while undercutting the policy behind our products liability law.

Federal district courts in Pennsylvania have offered conflicting opinions on the application of Comment k to manufacturing defect claims. For example, in Wagner v. Kimberly-Clark, 225 F.Supp. 3d 311 (E.D. Pa. 2016), the court considered whether Comment k barred strict liability design and manufacturing defect claims against a feeding tube manufacturer. The court began by acknowledging that the Pennsylvania Supreme Court has explicitly “declined to extend strict liability into the prescription drug arena” (quoting Lance v. Wyeth, 85 A.3d 434, 453 (Pa. 2014)). The court also acknowledged that the Pennsylvania Superior Court, in Creazzo, “applied Comment k to medical devices, ‘finding no reason why the same rationale applicable to prescription drugs may not be applied to medical devices.’” Despite this clear Pennsylvania precedent, the court “predicted” that the Pennsylvania Supreme Court would not apply Comment k to bar strict liability manufacturing defect claims against medical device manufacturers. This prediction was primarily based upon isolated dicta in Tincher v. Omega Flex, 104 A.3d 328 (Pa. 2014), where the Pennsylvania Supreme Court noted that “strict liability may be available with respect to any product, provided that the evidence is sufficient to prove a defect.” Wagner further justified its rejection of Comment k in the context of manufacturing defect claims by discounting Creazzo—not because it had been overruled or called into doubt—but because it had only been quoted once by the Pennsylvania Superior Court since it was issued in 2006. The Wagner court predicted that the Pennsylvania Supreme Court would narrow the application of Comment k, even though Pennsylvania appellate courts have never done so, and despite the Court’s continued recognition of Comment k in its 2014 Lance opinion.

In contrast, the U.S. District Court for the Eastern District of Pennsylvania has reached the opposite conclusion in other decisions, such as McLaughlin v. Bayer, 172 F.Supp. 3d 804 (E.D. Pa. 2016). There, the court held that medical device manufacturers are not subject to strict liability manufacturing defect claims under Pennsylvania law. McLaughlin emphasized that “the Pennsylvania Superior Court and numerous judges in the Eastern District of Pennsylvania have predicted that the Pennsylvania Supreme Court would extend Comment k to exclude medical devices from strict liability.” See also Kohn v. Ethicon, (E.D. Pa. Feb. 12, 2020) (holding that Pennsylvania does not recognize strict liability in products liability actions involving prescription medical devices); Drumheller v. Johnson & Johnson, (E.D. Pa. May 10, 2021) (holding that there is no “basis for distinguishing between prescription medical devices and prescription medical drugs for the purposes of applying Comment k.”).

An Exception to the Application of Comment k

The Pennsylvania Supreme Court’s decision in Tincher supports—rather than counsels against—continued application of Comment k’s unqualified immunity from strict liability. Any argument to the contrary overlooks Tincher’s broad call for judicial restraint in the development of Pennsylvania products liability law. While Tincher provided a necessary modernization of Pennsylvania products liability law and granted trial courts flexibility in managing the evidence in the trial of a strict liability case, Tincher did not invite trial courts to abandon established precedent unrelated to its core holdings. In fact, the court explicitly cautioned that its opinion should not be read as disturbing established principles of Pennsylvania’s products liability law unrelated to the new standards it articulated. Because the application of Comment k was not at issue in Tincher, the Pennsylvania Supreme Court’s admonition that established precedent remain in place supports the continued broad application of Comment k as a bar to strict liability. At least one federal trial court has noted that, notwithstanding the recent split over the application of Comment k to manufacturing defect claims, nothing in Tincher calls for a reexamination of the long-standing bar to strict liability claims for prescription drugs and medical devices. See Rosenberg v. C.R. Bard, 387 F. Supp.3d 572 (E.D. Pa. 2019).

In cases where courts have applied a non-existent exception to Comment k and allowed manufacturing defect claims to survive motion practice, they have done so reasoning that the Pennsylvania Supreme Court has not specifically addressed the viability of a strict liability manufacturing defect claim in the context of Comment k. But this should not matter. The Pennsylvania Supreme Court has adopted Comment k without exception and after more than 30 years, Pennsylvania’s appellate courts have not carved out exceptions to Comment k or otherwise narrowed its application.

Other cases have relied upon Comment k’s “properly prepared and marketed” language to conclude that Comment k does not apply to manufacturing defect claims. This interpretation is in direct conflict with established precedent from Pennsylvania’s appellate courts, which have unambiguously held that Comment k bars all strict liability claims. It also undermines the entire purpose of Comment k, which is to exclude certain products from strict liability and limit the available causes of action. Rather than narrowly focusing on particular terms, Comment k should be interpreted in a manner that is consistent with Pennsylvania law and promotes its sole purpose: limiting the available causes of action.

Policy and Precedent

Comment k is, by its terms and in its purpose, a claims-limiting principle intended to deprive plaintiffs of certain causes of action and afford drug and device manufacturers immunity from some claims. That a blanket application of Comment k to all strict liability causes of action, including manufacturing defect claims, may deprive some plaintiffs of a remedy or limit the claims available is not surprising. Indeed, that is the point.

Moreover, permitting a distinction between various strict liability claims is unworkable and inefficient, and leaves courts and parties playing a needless game of the “tail wagging the dog.” Although much ink has recently been spent litigating the viability of strict liability manufacturing defect claims in drug and device cases, few cases turn on a manufacturing defect claim. Most products liability cases brought against prescription drug and medical device manufacturers are failure to warn claims and have nothing to do with a deviation from the manufacturer’s intended design. Allowing an exception for manufacturing defect claims to what is a blanket prohibition on strict liability claims consumes time and judicial resources litigating the viability of a claim that is typically tangential to the gist of the action.

Reprinted with permission from the May 27, 2021 issue of The Legal Intelligencer. © 2021 ALM Media Properties, LLC. Further duplication without permission is prohibited. All rights reserved. For information, contact 877-257-3382 or or visit