The Sixth Circuit PBM Opioid Ruling Pulls Kentucky Into Federal Court as Polster Defends 800 Claims

The Sixth Circuit PBM opioid ruling issued on 18 September 2026 holds that the Commonwealth of Kentucky's lawsuit accusing pharmacy benefit managers of conspiring with manufacturers to expand the prescription opioid supply belongs in federal court, reversing a district court order that had sent the case back to state court. It landed one day after Judge Dan Aaron Polster, who presides over the opioid Multidistrict Litigation (MDL) in the Northern District of Ohio, filed his answer to a mandamus petition in which OptumRx and Express Scripts ask the same appellate court to undo his 27 July 2026 order letting roughly 800 plaintiffs add claims against them.

Read together, the two filings describe a single week in which the Sixth Circuit became the control point for both halves of the pharmacy benefit manager opioid question: where these cases are heard, and whether they may be heard together. No other publisher covering either development has put them side by side, and the tension between them is the thing practitioners need to price.

What the Sixth Circuit decided in Kentucky's PBM opioid case

Kentucky sued in state court. The Commonwealth's complaint, brought in Jessamine Circuit Court and later expanded to name OptumRx alongside Express Scripts, alleges that the PBMs used deceptive promotion to drive sales of highly addictive drugs, weakened the utilization-management controls that would have restrained prescribing and dispensing, and shipped opioids through mail-order pharmacies without adequate safeguards. The PBMs removed. The district court sent the case home. The Sixth Circuit, in Commonwealth of Kentucky v. Express Scripts, Inc., No. 25-5866, reversed that remand on 18 September 2026 and held the case belongs in federal court.

The panel did not have to break new ground, because the Sixth Circuit had already done so eight months earlier. In Ohio ex rel. Yost v. Ascent Health Services, LLC, No. 24-3033, decided 27 January 2026, the court considered Ohio's state-law pricing case against a group of health care firms including Express Scripts and Prime Therapeutics. Those PBMs had removed under the federal officer removal statute, 28 U.S.C. § 1442(a)(1), on the ground that the negotiating conduct Ohio attacked was performed in part under contracts to provide prescription drug coverage for federal beneficiaries. Ohio moved to remand, insisting its complaint reached no conduct directed by a federal officer and disclaiming any challenge to the administration of federal health programs. The Sixth Circuit held that the PBMs were persons "acting under" federal officers because the negotiations at issue were carried out under detailed federal supervision, and reversed.

Yost is precedential. Kentucky, decided under the same statute against two of the same defendants on a materially similar removal record, followed it.

Why PBM opioid lawsuits keep ending up in federal court

The federal officer removal statute is the mechanism, and it is worth stating plainly because it does not work the way ordinary removal does. Section 1442(a)(1) lets a defendant move a case to federal court when it was sued for acts performed while acting under an officer or agency of the United States and can raise a colorable federal defense. Unlike diversity or federal question removal, it does not require complete diversity, it does not require a federal claim on the face of the complaint, it is construed broadly rather than narrowly, and a remand order rejecting it is appealable — which is why these disputes reach the courts of appeals at all.

The PBMs' theory is structural. Express Scripts and OptumRx negotiate rebates and build formularies for commercial clients and, simultaneously, for federal programs: the Department of Defense's TRICARE, the Office of Personnel Management's federal employee health benefits arrangements, and the Department of Veterans Affairs. The same negotiating team, the same rebate contract with the same manufacturer, the same formulary decision. That is the point on which the state and municipal plaintiffs keep losing.

Plaintiffs' counsel have tried to solve the problem by amendment. In the New York cases the counties inserted broad disclaimers purporting to abandon any claim arising out of the defendants' federal work. The Second Circuit was unpersuaded in County of Westchester v. Express Scripts, No. 24-1639, decided 2 September 2026, and the reason it gave is the one that now recurs: the PBMs do not keep separate federal and non-federal books of business, the negotiations with manufacturers were singular, and the community-wide harms alleged are themselves indivisible. A disclaimer cannot carve apart conduct that was never carved apart in the first place. The Sixth Circuit had reached the same conclusion about Ohio's disclaimer in Yost, and the Eighth Circuit had reached it about Arkansas's in Griffin v. OptumRx, Inc., No. 25-1165, decided 6 May 2026.

For a plaintiffs' firm running a public-entity inventory, the operational lesson is unattractive but clear: pleading around the federal relationship has now failed in three circuits, and drafting a narrower complaint is not obviously a cure when the indivisibility rationale attaches to the defendant's operations rather than to the plaintiff's words.

Which courts have ruled on PBM opioid removal, and do they agree?

They agree. Four federal appellate courts have now accepted federal officer jurisdiction over claims against PBMs arising from formulary and rebate conduct, and none of the decisions below is an outlier.

Decision	Court	Date	Plaintiff	Outcome
Puerto Rico v. Express Scripts, Inc.	First Circuit	2024	Commonwealth of Puerto Rico	Federal officer jurisdiction approved (drug pricing)
Ohio ex rel. Yost v. Ascent Health Services, LLC, No. 24-3033	Sixth Circuit	27 January 2026	State of Ohio	Remand reversed; PBMs acted under federal officers
Griffin v. OptumRx, Inc., No. 25-1165	Eighth Circuit	6 May 2026	State of Arkansas	Remand reversed; disclaimers could not sever federal duties
County of Westchester v. Express Scripts, No. 24-1639	Second Circuit	2 September 2026	New York counties	§ 1442(a)(1) jurisdiction found; disclaimers ineffective
Commonwealth of Kentucky v. Express Scripts, Inc., No. 25-5866	Sixth Circuit	18 September 2026	Commonwealth of Kentucky	Remand reversed; case belongs in federal court

Individual district courts have gone the other way — a Western District of Virginia court granted a city's remand motion and returned PBM claims to state court — but appellate authority is running one direction, and it is running toward a single federal forum. Once a PBM opioid case is in federal court it is a tag-along candidate for the opioid MDL, which is precisely what makes the second half of this week's news consequential.

What Express Scripts and OptumRx are asking the Sixth Circuit to do

The petition in In re OptumRx, Inc., No. 26-3780, docketed on 27 August 2026, seeks a writ of mandamus vacating Judge Polster's 27 July 2026 order. That order permitted roughly 800 plaintiffs already in In re National Prescription Opiate Litigation, MDL No. 2804, to amend their complaints to add claims against the two PBMs. The petitioners' framing, as reported, is that the order forces two of the largest remaining defendants in the litigation either to settle for enormous sums or to litigate hundreds of cases for years, and that an MDL court has no license to reach that result by departing from the Federal Rules of Civil Procedure. Lawyers for Civil Justice, the defense-side rules organization, filed in support, casting the question as whether MDLs are governed by the Rules at all.

The Sixth Circuit did not summarily deny the petition. On 1 September 2026 it ordered the Plaintiffs' Executive Committee in MDL 2804 to respond — an instruction the court issues when a petition is at least worth briefing.

Judge Polster's own answer followed on 17 September 2026. He rejected what he characterized as the PBMs' spurious insinuations about his motives and warned that granting the writ and breaking the consolidated suits apart would produce disarray across the MDL. That is a sharper posture than a district judge ordinarily adopts toward a petition nominally directed at him, and it reflects how much of the remaining docket is riding on the answer.

Date	Step
27 July 2026	Judge Polster permits roughly 800 MDL 2804 plaintiffs to amend to add PBM claims
27 August 2026	OptumRx and Express Scripts docket a mandamus petition, No. 26-3780
1 September 2026	Sixth Circuit orders the Plaintiffs' Executive Committee to respond
17 September 2026	Judge Polster answers, warning of disarray if the suits are broken apart
18 September 2026	Sixth Circuit reverses remand in the Kentucky PBM opioid case

Can an MDL judge let hundreds of plaintiffs add a new defendant this late?

Sometimes, and the Sixth Circuit is the court that has already said no once. In In re National Prescription Opiate Litigation, 956 F.3d 838 (6th Cir. 2020), the court granted mandamus and ordered amendments stricken after the MDL court allowed two Ohio counties to add dispensing claims against pharmacy defendants some nineteen months after the deadline for amendment and after discovery and summary judgment briefing on those claims had closed. The opinion's durable sentence is that there is no "MDL exception" to the Federal Rules: transfer under 28 U.S.C. § 1407 consolidates cases for pretrial purposes, but each constituent action keeps its individual character, and a determination of the parties' rights must rest on the same legal rules that would govern anywhere else.

That precedent is the spine of the 2026 petition, and it is why the petition is not frivolous even though mandamus is an extraordinary remedy. The plaintiffs' answer has to be that 2020 involved untimely amendments against defendants already litigating summary judgment on the very claims being added, whereas the PBM track is a distinct and later-developing set of allegations against defendants brought into the litigation on a different schedule. Whether the Sixth Circuit accepts that distinction is the whole case.

Two structural points are worth separating. Timeliness under Rule 15 and Rule 16 is one question. Whether an MDL transferee court may manage a late-added defendant track through case management orders rather than case-by-case rulings is another, and it is the question Lawyers for Civil Justice is really pressing. A ruling confined to the first would be an ordinary correction. A ruling that reaches the second would change how every large MDL adds defendants.

What happens to the 800 amended complaints if the petition succeeds

Nothing about a mandamus grant would extinguish the underlying claims on the merits. The amendments would be stricken, and each affected plaintiff would be returned to its pre-amendment complaint, free to sue the PBMs in a separate action. The practical problem is what that separate action costs.

It costs time, because a newly filed case restarts service, pleading and motion practice that the MDL had absorbed. It costs leverage, because a plaintiff outside the consolidated PBM track has none of the discovery already produced and none of the aggregate settlement pressure that comes from being one of 800. And, for some plaintiffs, it may cost the claim outright, because the Statute of Limitations on these theories has already proved fatal to at least one major municipality. The City of Boston's PBM opioid suit was dismissed as untimely, and the dismissal was affirmed on appeal this year, on reasoning that Boston knew enough about the PBMs' role well before it sued given that it had filed against manufacturers years earlier. Any public entity that relied on being inside the MDL amendment, rather than filing its own action, is exposed to the same argument.

This is the asymmetry that makes the week's two developments pull against each other. The removal decisions push every PBM opioid case toward one federal forum. The mandamus petition, if granted, would fragment the cases already inside that forum. The PBMs are, in effect, arguing for centralized jurisdiction and against centralized treatment.

When will PBM opioid claims actually be tried?

Not soon, and not first in the MDL. The nearest firm trial setting against the PBM defendants is in state court: Jefferson County, Missouri's case against Express Scripts, OptumRx and Caremark has a 2027 trial date. Judge Polster has opened a bellwether track against Express Scripts and OptumRx within MDL 2804, but no Bellwether Trial against the PBMs has produced a verdict, and the mandamus petition has to be resolved before the composition of the PBM track is even stable.

That matters for valuation. In a Mass Tort of this size, settlement values are anchored by tried outcomes, and the PBM segment of the opioid litigation has none. Manufacturers, distributors and pharmacies have all been through verdicts or Global Settlement negotiations that produced public numbers. The PBMs have not, which is why both sides are fighting this hard over procedure: procedure is currently the only thing setting the price.

What it means for the parties and their counsel

For state and municipal plaintiffs, the removal line is now settled enough to plan around. Disclaimers have failed in three circuits, and filing in state court should be treated as a routing decision rather than a forum choice. Public entities that are not already plaintiffs in their own right, and that have been relying on an MDL amendment for their PBM claims, should be running a limitations analysis now rather than after the Sixth Circuit rules on the petition.

For PBM defense teams, the two-front posture is deliberate but not cost-free. Establishing that PBMs act under federal officers for removal purposes is a jurisdictional win that necessarily emphasizes how integrated the federal and commercial books of business are — the same indivisibility that defeats plaintiffs' disclaimers is also a factual admission about how these companies operate, and it will be quoted back in merits discovery.

For anyone drafting or contesting case management orders in a large MDL, the petition is the live test of how far a transferee court may go in adding a defendant track by order. The 2020 opinion set the outer boundary; In re OptumRx will show whether the Sixth Circuit reads that boundary narrowly or as a general instruction that consolidated management cannot substitute for case-specific rulings.

For the Judicial Panel on Multidistrict Litigation (JPML) and for courts managing other aggregate dockets, the sequence is a reminder that removal doctrine and aggregation doctrine are not independent levers. Expanding the federal forum without a stable answer on aggregation simply relocates the problem.

Frequently asked questions

What did the Sixth Circuit decide in Kentucky's PBM opioid case?

On 18 September 2026, in Commonwealth of Kentucky v. Express Scripts, Inc., No. 25-5866, the Sixth Circuit held that Kentucky's suit alleging that pharmacy benefit managers conspired with manufacturers to increase the prescription opioid supply belongs in federal court, and reversed the district court's order remanding it to state court.

Why can pharmacy benefit managers remove opioid cases to federal court?

Because of the federal officer removal statute, 28 U.S.C. § 1442(a)(1). Courts have held that when PBMs negotiate rebates and manage formularies under contracts with TRICARE, the Office of Personnel Management and the Department of Veterans Affairs, they are acting under federal officers, and the state-law claims attacking that negotiating conduct are therefore removable.

Does disclaiming federal-program claims defeat removal?

It has not worked. The Second, Sixth and Eighth Circuits each rejected disclaimers because the PBMs did not maintain separate federal and non-federal books of business, the manufacturer negotiations were singular, and the harms alleged were indivisible.

What are the PBMs asking the Sixth Circuit to do in the opioid MDL?

In In re OptumRx, Inc., No. 26-3780, OptumRx and Express Scripts seek a writ of mandamus vacating Judge Polster's 27 July 2026 order, which allowed roughly 800 plaintiffs in MDL No. 2804 to amend their complaints to add claims against them.

What happens to those 800 claims if the mandamus petition is granted?

The amendments would be stricken rather than the claims decided. Affected plaintiffs could file separate actions against the PBMs, but would lose the benefit of consolidated pretrial treatment and would face limitations arguments of the kind that defeated the City of Boston's PBM opioid suit.

Has any PBM opioid case been tried?

No verdict has been returned against the PBM defendants in the opioid litigation. The nearest firm setting is Jefferson County, Missouri's state-court case against Express Scripts, OptumRx and Caremark, scheduled for 2027.