“Due To” Means “Because Of”: The Fourth Circuit’s But-For Causation Test for ERISA Limitation Clauses in Penland v. Metropolitan Life

Introduction

In Tracy Penland v. Metropolitan Life Insurance Company, No. 24-1772 (4th Cir. 2025), the Fourth Circuit revisited a long-running ERISA disability dispute. The case centers on whether a participant who has already received twenty-four months of long-term disability (“LTD”) benefits can continue to receive them when the plan’s limitation clause caps benefits for disabilities “due to” certain enumerated conditions (here, musculoskeletal disorders) unless the claimant supplies objective evidence of an exempting diagnosis such as radiculopathy. The panel (Judge Wynn writing, joined by Judges Harris and Benjamin) affirmed the district court’s Rule 52 judgment for MetLife, fleshing out two important principles:

“Due to” in a limitation clause invokes ordinary, but-for causation; the limited condition need not be the sole cause of disability.
The claimant bears the burden of producing objective medical evidence to escape a limitation, and conclusory or purely subjective records will not suffice.

Although the decision is unpublished, it crystallises how courts in the Fourth Circuit will now analyze causation language in ERISA plans and apply Tekmen v. Reliance Standard’s procedural regime after remand.

Summary of the Judgment

Penland, a former employee who ceased working in 2015, initially received LTD benefits. The plan limited lifetime benefits to 24 months if disability was caused by “mental or nervous disorders,” “musculoskeletal or soft-tissue disorders,” or similar conditions, unless the claimant could show objective evidence of radiculopathy or other specified diagnoses. MetLife terminated benefits in 2021, concluding that Penland’s continuing impairment was “due to” musculoskeletal conditions and that he failed to show objective radiculopathy. The district court (on remand after Tekmen) conducted a Rule 52 bench trial on the administrative record and upheld MetLife’s decision.

On appeal Penland argued:

The limitation clause applied only if the excluded condition was the sole cause of disability;
He had in fact supplied objective evidence of radiculopathy;
The district court improperly discounted his treating nurse’s opinion and mis-weighed other evidence.

The Fourth Circuit rejected each argument, holding:

“Due to” carries its ordinary meaning of “because of,” adopting a but-for test and rejecting a sole-cause interpretation.
Penland’s records did not include imaging or physician explanations sufficient to prove radiculopathy objectively.
The district court permissibly credited independent medical consultants over conclusory treating-provider statements, consistent with Black & Decker Disability Plan v. Nord.

Accordingly, the panel affirmed the district court; Penland remains ineligible for further LTD benefits under the plan.

Analysis

1. Precedents Cited

Tekmen v. Reliance Standard Life Ins. Co., 55 F.4th 951 (4th Cir. 2022) – Abolished “ERISA summary-judgment” shortcuts; district courts must apply Fed. R. Civ. P. 52 bench-trial procedures when reviewing benefit denials. Penland is one of the first published applications after a Tekmen remand.
Johnson v. American United Life Ins. Co., 716 F.3d 813 (4th Cir. 2013); Wheeler v. Dynamic Eng’g and United McGill Corp. v. Stinnett – Together establish that ERISA plans are contracts interpreted by ordinary meaning.
Bostock v. Clayton County, 590 U.S. 644 (2020) – Cited for the proposition that “because of” imports but-for causation and may admit multiple causes.
Black & Decker Disability Plan v. Nord, 538 U.S. 822 (2003) – Clarifies that ERISA administrators (and reviewing courts) need not give treating physicians special deference.

These authorities anchored the court’s interpretive framework and rebutted each of Penland’s arguments.

2. Legal Reasoning

The opinion proceeds in three logical steps:

Contract Interpretation of “Due To”.
- Applying Johnson, the panel looked to ordinary meaning.
- Bostock teaches that “because of” requires but-for, not sole causation, and may encompass multiple contributing causes.
- Therefore, once any limited condition is a but-for cause, the limitation clause is triggered, absent an applicable exception.
Objective-Evidence Exception (Radiculopathy).
- The plan exempts disabilities “due to” musculoskeletal disorders when objective evidence shows radiculopathy.
- Penland’s submissions—Dr. Patel’s notes repeating earlier diagnoses—were conclusory; the MRI images and formal reports were not in the record.
- Independent consultants (Drs. Pietruszka & Natanzi) expressly found no objective radiculopathy; the district court’s crediting of those opinions was not clearly erroneous.
Burden of Proof and Weighing Evidence.
- Penland bore the burden of demonstrating continuing disability under non-limited conditions.
- The court rejected a treating-physician preference, following Nord.
- It found Penland’s nurse’s two-page letter conclusory and gave greater weight to detailed, document-citing consultant reports.
- Without functional limitations from non-limited conditions, Penland could not prove incapacity to earn >60% predisability income.

3. Impact

Although designated “unpublished,” the decision will likely influence ERISA litigation inside and outside the Fourth Circuit in several ways:

Standardised Causation Test. Plan drafters often use “due to,” “caused by,” or “resulting from.” Penland cements that, at least in the Fourth Circuit, such language invokes a but-for standard that may encompass multiple contributing conditions, thwarting claimants’ “sole cause” theories.
Objective Evidence Requirements. The case underscores that to escape musculoskeletal limitations, claimants must supply actual imaging or nerve-conduction studies, not merely physicians’ shorthand references.
Post-Tekmen Procedure. Penland offers a clear roadmap for district courts conducting Rule 52 reviews: make explicit findings on (i) plan interpretation; (ii) medical evidence; (iii) credibility and weight; and (iv) vocational impact.
Strategic Guidance for Practitioners. Claimants should compile full diagnostic studies before litigation. Administrators should ensure clear articulation of review rationales and preserve consultant independence to withstand Tekmen scrutiny.

Complex Concepts Simplified

ERISA §502(a)(1)(B). Allows plan participants to sue for benefits due under a plan.
Rule 52 Bench Trial. After Tekmen, courts decide ERISA disputes on the paper record, issuing findings of fact and conclusions of law rather than using summary-judgment standards.
But-For Causation. An event (disability) is “due to” a condition if the event would not have occurred but for that condition, regardless of other contributing factors.
Radiculopathy. Disease of spinal nerve roots producing objective neurological signs (e.g., via MRI or EMG). Plans often treat it differently from generic back pain.
Objective vs. Subjective Evidence. Objective: measurable tests, imaging, clinical signs. Subjective: patient-reported pain, fatigue. Many LTD plans require objective proof to avoid abuse.

Conclusion

Penland v. Metropolitan Life adds an important gloss to ERISA LTD jurisprudence. By equating “due to” with ordinary but-for causation, the Fourth Circuit forecloses arguments that limitation clauses activate only when a single, excluded condition is the exclusive cause of disability. Coupled with its strict reading of the objective-evidence exception and its faithful adherence to Nord and Tekmen, the decision reinforces contract-based interpretation while providing litigants with concrete procedural and evidentiary benchmarks. Going forward, both claimants and administrators in the Fourth Circuit must tailor their strategies—and documentary records—around these clarified standards.