A few weeks ago, we found ourselves underwhelmed by the court’s Rule 702 rulings in the Covidien Hernia Mesh MDL. Today, we can say much the same thing about its summary judgment decision. In In re: Covidien Hernia Mesh Products Liability Litigation No. II, 2026 WL 1555914 (D. Mass. June 2, 2026), the court largely denied summary judgment in a bellwether case governed by Alabama law. In fact, every claim survived except for design defect, on which the court reserved judgment pending a ruling on whether plaintiff may rely on a new alternative-design opinion offered only after his original expert opinions were excluded.
While we have concerns with several aspects of the decision, the court’s treatment of comment k is the most troubling.
Comment k to the Restatement recognizes that some products are “unavoidably unsafe” and therefore should not be subject to design defect liability. The Alabama Supreme Court has repeatedly applied comment k categorically to prescription drugs. The question presented here was whether the same rule applies to prescription medical devices.
The answer should not have been difficult. Alabama courts have never held that medical devices should be treated differently than prescription drugs under comment k. Indeed, the one Alabama federal court to squarely address the issue applied the same categorical approach to both. More broadly, our research has shown that states overwhelmingly apply the same comment k framework to prescription drugs and prescription medical devices, whether that framework is categorical or case-by-case.
But the Covidien Mesh MDL court charted a different course (an unfortunate recent MDL trend). Rather than follow Alabama precedent treating prescription products similarly, or the overwhelming authority from other jurisdictions that do the same, the court relied on what is essentially an outlier decision from Utah that distinguished between drugs and devices for comment k purposes. The result was a prediction that Alabama would apply comment k to medical devices on a case-by-case basis, even though no Alabama appellate court has ever done so. Id. at *6-7.
That prediction is particularly difficult to square with the Erie doctrine. Federal courts sitting in diversity are not supposed to innovate or expand state law. Their task is to predict what the state’s highest court would do. Here, the court reasoned that because many states employ a case-by-case comment k analysis, Alabama would likely do the same for medical devices. Id. at *7. But that is not how Erie works. The relevant question is not what most states do. The question is what Alabama would do. And the best evidence of that answer is Alabama’s own precedent, which consistently applies comment k categorically to prescription drugs and has never suggested medical devices should be treated differently. If anything, applying a rule of “sameness” to medical devices would have been the more conservative prediction and the one less likely to expand state tort liability beyond existing precedent.
For now, the practical effect of the ruling remains uncertain. The court reserved final judgment on the design defect claim because plaintiff’s original alternative-design opinions were excluded under Rule 702. Plaintiff has since attempted to fill that gap with a new expert affidavit offering a different alternative design. Whether that late-breaking effort survives remains to be seen.
The rest of the decision is similarly generous to plaintiff.
Plaintiff’s failure-to-warn claim focused on the device’s collagen barrier, which is intended to reduce adhesions during the healing process. Plaintiff contended that defendant failed to warn that the barrier could degrade within seven days. The problem with that argument is that the Instructions for Use expressly warned about the very complications plaintiff allegedly suffered–adhesions, bowel obstruction, and hernia recurrence. Id. at *8. The court nevertheless found a jury question because the warnings did not address the alleged “degree of danger.” Id. at *9. We are struggling to understand how a warning can be deemed inadequate when it warns physicians of the precise injuries that allegedly occurred. If a manufacturer identifies the relevant risks and the warned-of complications occur, one would think the warning accomplished exactly what it was supposed to do.
It also seems to support a finding that prescription medical devices, like prescription drugs, are unavoidably unsafe. There is no guarantee that every surgery will be 100% effective. So, manufacturers warn about the risks. Surgeons assess those risks, using their independent medical knowledge and their knowledge of the patient, and make treatment decisions. When the risk that occurs is one that is warned about there can be neither design or warning defect liability.
The court’s causation analysis is equally difficult to follow. The implanting surgeon testified that he never read the IFU and would not have changed his decision to use the mesh. Id. at *10. Under Alabama’s learned intermediary doctrine, that testimony should ordinarily end the failure-to-warn claim because an unread warning cannot have affected the physician’s decision-making. Not here. The court concluded that causation could instead be established through alleged, but unidentified, statements by defendant’s sales representatives regarding the longevity of the collagen barrier. The evidentiary basis for this theory came from yet another late-filed declaration, this time from the implanting surgeon himself. Even then, the surgeon did not recall any representative actually making the alleged misstatement. Rather, the court held that a jury could infer the statements were made because sales representatives had been trained that the barrier could last up to thirty days. Id. at *10.
That is a remarkable chain of inferences. Representatives were trained on a topic, therefore they must have communicated it to this surgeon, therefore the surgeon must have relied on it, despite not specifically recalling the communication. Yet those inferences were enough not only to preserve the failure-to-warn claim, but also plaintiff’s fraud and punitive damages claims. Id. at *11, *13.
Finally, the decision contains a cautionary tale about MDL case-management agreements. Alabama’s implied-warranty statute requires notice. Here, the court held that an email adding plaintiff to an MDL tolling agreement satisfied that statutory requirement. Id. at *12. Defendants often enter into MDL-wide agreements for practical reasons and to streamline litigation. This ruling serves as a reminder that such agreements can sometimes reappear later in entirely unexpected contexts.
Taken together, the opinion reflects a recurring theme. At multiple junctures, the court was willing to make Erie predictions that expanded state law, draw inferences unsupported by direct evidence, and overlook evidentiary shortcomings that ordinarily would doom a claim. Perhaps some of those rulings will ultimately prove academic if plaintiff cannot supply admissible evidence of a safer alternative design. But for now, this bellwether decision stands as another example of an MDL court finding a way to keep virtually every claim alive for another day.






