APA Limitations Accrual for Pre-Enforcement Facial Challenges: Injury Occurs at Rule Promulgation, Not Later Enforcement Signals

I. Introduction

In Henry McMaster v. United States Department of Labor (4th Cir. June 24, 2026), South Carolina’s Governor and the South Carolina Department of Labor, Licensing and Regulation challenged (among other things) OSHA’s 2016 interim final rule requiring state-plan States to maintain civil penalties at least as high as federal OSHA’s inflation-adjusted penalties. The case arose from the federal-state “state plan” framework under the Occupational Safety and Health Act, which allows States to administer their own occupational safety and health programs so long as they remain “at least as effective” as the federal program.

The central procedural issue on appeal was timeliness: whether the State’s Administrative Procedure Act (“APA”) facial challenge to the 2016 rule—filed in March 2023—was barred by the six-year statute of limitations in 28 U.S.C. § 2401(a). Plaintiffs argued their claim did not accrue until 2022, when OSHA issued a formal FAME “finding” that South Carolina was noncompliant, allegedly creating a “credible threat” of enforcement.

II. Summary of the Opinion

The Fourth Circuit affirmed dismissal of the two APA counts as untimely. Relying heavily on Corner Post, Inc. v. Board of Governors of Federal Reserve System, the court held that an APA claim accrues when the plaintiff is injured by final agency action—here, when OSHA promulgated the 2016 interim final rule that put South Carolina out of compliance. A later compliance “finding” in 2022 did not restart or newly trigger the limitations period for a pre-enforcement facial challenge.

The court also emphasized a practical safety valve: even if a party is time-barred from bringing a pre-enforcement facial challenge, it may still contest the legality of the regulation defensively in a later enforcement proceeding.

III. Analysis

A. Precedents Cited

1. Corner Post, Inc. v. Board of Governors of Federal Reserve System

Corner Post supplied the governing limitations framework. The Supreme Court interpreted 28 U.S.C. § 2401(a) to mean an APA cause of action “accrues” when the plaintiff has “a complete and present cause of action”—i.e., when the plaintiff has the right to sue and obtain relief. In the APA context, that is when the plaintiff is injured by final agency action.

Plaintiffs invoked Corner Post to argue that their “injury” did not occur until 2022. The Fourth Circuit rejected the analogy: unlike the plaintiff in Corner Post (an entity not yet in existence when the rule issued), South Carolina existed and was affected immediately when the 2016 rule was promulgated and began operating to render the State plan noncompliant.

2. Director, Office of Workers' Compensation Programs v. Newport News Shipbuilding & Dry Dock Co.

The court cited this decision for the foundational APA proposition that a litigant must show “at the outset of the case” that it is injured in fact by agency action. This anchors the court’s view that “injury” is not an optional or elastic concept that can be deferred for strategic limitations purposes; it is a threshold requirement that, once satisfied, triggers accrual under § 2401(a) as framed by Corner Post.

3. Abbott Labs. v. Gardner

Abbott Labs. is the canonical pre-enforcement review case. The Fourth Circuit used it to underscore that regulated parties can often sue upon promulgation of a rule (before an enforcement action), because the legal consequences and compliance pressures created by the rule itself can constitute sufficient injury.

This mattered because Plaintiffs’ theory depended on the opposite premise: that they lacked standing (and thus no “complete and present” cause of action) until OSHA later signaled more imminent enforcement in 2022.

4. Bryant v. Woodall

Plaintiffs leaned on Bryant for the “credible threat” concept often used in pre-enforcement challenges, contending that OSHA’s earlier pattern of “sustained nonenforcement” blunted any credible threat until the 2022 finding. The Fourth Circuit did not accept that this reframed accrual. The opinion treats “credible threat” as relevant to standing in certain contexts, but not as a mechanism to postpone accrual when the plaintiff concedes it was injured—and could have sued—when the rule was published.

5. Hire Order Ltd. v. Marianos

The court cited Hire Order for the proposition that the limitations period begins to run when an agency publishes a regulation, not when the regulation becomes effective. While noting Hire Order was “abrogated on other grounds” by Corner Post, the publication-date rule remained functionally consistent with the court’s analysis here because South Carolina’s suit was late under either date (interim final rule in 2016 or final rule in 2017).

6. Poe v. Ullman, Doe v. Duling, and Doe v. Bolton

These cases were deployed to evaluate Plaintiffs’ suggestion that any enforcement threat had “expired.” The court contrasted moribund or rarely enforced laws (Poe, Doe v. Duling) with laws that are “recent and not moribund” (Doe v. Bolton), implying it is implausible to treat a 2016 federal regulatory mandate as having become non-threatening merely because OSHA’s enforcement escalation was gradual.

Importantly, the court’s key point was temporal: even if a threat had dissipated, that would not erase that the claim “first accrued” when the rule inflicted the initial injury.

7. Herr v. U.S. Forest Service (quoted via Corner Post)

The court relied on this principle—endorsed in Corner Post—that regulated parties “may always assail a regulation as exceeding the agency's statutory authority in enforcement proceedings against them.” This supports the court’s broader equitable framing: strict limitations for pre-enforcement facial challenges do not foreclose all avenues of judicial review.

8. McMaster v. Dep't of Lab.

The district court’s decision framed the dilemma: either Plaintiffs were never credibly threatened (no standing) or they were injured in 2016 (but time-barred). On appeal, Plaintiffs pursued the “later injury” theory; the Fourth Circuit’s opinion effectively adopts the district court’s injury-in-2016 view for accrual purposes, reinforced by Plaintiffs’ oral-argument concession.

B. Legal Reasoning

  1. Identify the governing limitations rule. The court applied 28 U.S.C. § 2401(a): suits against the United States are barred unless filed within six years after the “right of action first accrues.”
  2. Define accrual in the APA setting. Under Corner Post, accrual occurs when the plaintiff has a complete and present cause of action—i.e., when injured by final agency action.
  3. Locate the injury in time. The court treated OSHA’s 2016 interim final rule as the injury-triggering event because it immediately put South Carolina “out of compliance” by requiring state penalties to match federal levels. Plaintiffs conceded at oral argument that the first credible threat arose from publication of the rule.
  4. Reject “second injury” accrual and “nonenforcement” reset theories. Even if OSHA’s enforcement posture was gradual, a later FAME “finding” in 2022 was not an enforcement proceeding and did not create a new accrual date for a pre-enforcement facial challenge. Accrual is keyed to when the right of action “first accrues,” not when enforcement becomes more likely.
  5. Preserve defensive challenges. The court emphasized that time-barring a pre-enforcement facial suit does not prevent a party from contesting ultra vires regulations defensively in enforcement proceedings.

C. Impact

  • Constrains late-filed facial APA challenges by States and regulated entities. A later compliance warning, monitoring report, or “finding” generally will not restart the six-year clock if the plaintiff was already injured by the rule upon promulgation.
  • Clarifies Corner Post’s reach. The decision narrows attempts to treat Corner Post as a broad invitation to re-time APA claims; it reinforces that the “new plaintiff” logic in Corner Post differs from “existing plaintiff, delayed enforcement” situations.
  • Encourages earlier litigation strategy decisions for state-plan States. When federal rulemaking changes the conditions of state-plan approval (e.g., penalty parity), States must either sue within six years or accept that their principal route will be defensive litigation if/when formal revocation or withdrawal proceedings occur.
  • Channels disputes into enforcement/revocation proceedings. By characterizing the 2022 “finding” as non-enforcement, the opinion signals that judicial review of the rule’s legality may be postponed to (and shaped by) the procedural posture of an actual enforcement or revocation action.

IV. Complex Concepts Simplified

State-plan States / “at least as effective”
Some States run their own OSHA-style workplace safety programs. To keep that authority, their standards and enforcement—including penalties—must be at least as strong as federal OSHA’s.
Final agency action
An agency action that marks the consummation of the agency’s decision-making and has legal consequences. Here, OSHA’s rule requiring state penalty parity had immediate compliance consequences for South Carolina’s state plan.
Accrual (statute of limitations)
The moment the clock starts. Under Corner Post, an APA claim accrues when the plaintiff is injured by final agency action—when the plaintiff can file suit and seek relief.
Pre-enforcement facial challenge
A lawsuit attacking a rule before the government brings an enforcement action, typically arguing the rule is invalid in all (or most) applications.
Credible threat of enforcement
A standing concept often used in pre-enforcement cases: plaintiffs must show more than speculative fear. The court held that even if later events sharpen the threat, that does not change when a claim “first accrues” if the plaintiff was already injured by the rule.
Defensive challenge in enforcement proceedings
Even if you can’t sue proactively due to a limitations bar, you can still argue the regulation is unlawful when the government tries to enforce it against you.

V. Conclusion

The Fourth Circuit’s decision establishes a clear timing rule for APA facial challenges in this context: when a regulation’s promulgation immediately places a regulated party (including a State plan) out of compliance, the six-year clock under 28 U.S.C. § 2401(a) starts then—not when the agency later issues monitoring “findings” or signals heightened enforcement. While this tightens the window for pre-enforcement review, the court underscored that parties retain the ability to contest an allegedly ultra vires regulation defensively if and when enforcement proceedings are brought.