Bayer & Janssen v. Mylan: XARELTO® Patent Dispute Dismissed With Prejudice
Bayer AG and Janssen Pharmaceuticals filed suit against Mylan NV in Delaware over US10828310B2, a patent covering 2.5 mg rivaroxaban (XARELTO®) tablets. After 1,184 days of litigation, the parties filed a joint stipulation dismissing all claims with prejudice — each side bearing its own costs and attorneys’ fees.
A three-year ANDA patent battle ends by mutual stipulation
On 21 September 2022, Bayer AG and Janssen Pharmaceuticals, Inc. filed suit against Mylan NV and Mylan Inc. in the United States District Court for the District of Delaware before Judge Richard G. Andrews. The plaintiffs asserted US10828310B2 — a patent directed to 2.5 mg rivaroxaban tablet formulations sold under the blockbuster brand XARELTO® — in response to Mylan’s effort to bring a generic version of that product to market.
On 18 December 2025, the parties filed a joint stipulation pursuant to Federal Rules of Civil Procedure 41(a)(1) and 41(c), dismissing all claims and defenses asserted by both sides with prejudice. The with-prejudice designation means neither Bayer/Janssen nor Mylan may revive the same claims in a future proceeding. Each party agreed to bear its own costs, disbursements, and attorneys’ fees, suggesting a negotiated resolution rather than a unilateral capitulation by either side.
The 1,184-day duration — spanning more than three years — is consistent with contested ANDA pharmaceutical patent litigation, though the ultimate stipulated dismissal suggests the parties reached a commercial accommodation before trial. The specific terms of any underlying agreement, including potential authorised-generic arrangements or entry dates, are not disclosed in the public record. What drove the timing of the resolution and whether any market-access understanding was reached remain unknown from the docket alone.
Filing to Dismissed with Prejudice in 1184 days
1,184 days — over three years from filing to dismissal, lengthy for a stipulated resolution
Dismissed with prejudice: what the stipulation means for both parties
Rule 41 stipulated dismissal with prejudice explained
A dismissal with prejudice under FRCP Rules 41(a)(1) and 41(c) is a final adjudication on the merits — it permanently extinguishes the dismissed claims. Unlike a without-prejudice dismissal, neither party can refile the same claims in a new action. The stipulated nature signals mutual agreement rather than a court-ordered outcome, and typically reflects an underlying commercial resolution not visible in the public docket.
Permanent bar on refilingXARELTO® patent survives without judicial validity ruling
For Bayer and Janssen, the with-prejudice dismissal means US10828310B2 was never adjudicated invalid or unenforceable by the court. The patent remains on the register and retains its presumption of validity. Bayer and Janssen can continue to assert it against other potential generic entrants. However, the absence of a merits win also means no injunction or damages precedent was established.
Patent validity preservedMylan forfeits the right to re-challenge on these same grounds
The with-prejudice stipulation bars Mylan from reasserting its counterclaims — including any invalidity or non-infringement defences raised in this action — against the plaintiffs in a subsequent proceeding. In ANDA litigation, this typically signals that Mylan negotiated some form of market access arrangement, though no such terms are publicly disclosed. The own-costs provision suggests neither party claimed a clear litigation win.
Counterclaims extinguishedBrand-generic settlement dynamics in the anticoagulant market
Stipulated dismissals in ANDA pharmaceutical cases frequently accompany authorised-generic agreements, consent judgments, or negotiated market-entry dates. For the 2.5 mg rivaroxaban segment — a dose used specifically in cardiovascular risk reduction — any agreed generic entry would have significant downstream pricing implications. Other generic filers watching this case should note that the patent itself remains unchallenged in this record.
Possible authorised-generic dealFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Bayer AG | Company | Pharmaceutical IP holders — asserting US10828310B2 covering 2.5 mg XARELTO® rivaroxabanSearch in Eureka ↗ |
| Co-Plaintiff | Janssen Pharmaceuticals, Inc. | Company | Search in Eureka ↗ |
| Co-Plaintiff | Bayer AG | Company | Search in Eureka ↗ |
| Defendant | Mylan, NV | Company | Generic pharmaceutical manufacturer seeking market entry with 2.5 mg rivaroxaban tabletsSearch in Eureka ↗ |
| Co-Defendant | Mylan, Inc. | Company | Search in Eureka ↗ |
| Plaintiff counsel | Alexander S. Zolan | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff counsel | Derek James Fahnestock | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff counsel | Dov P. Grossman | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff counsel | Kathryn S. Kayali | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff law firm | Morris, Nichols, Arsht & Tunnell LLP | Law Firm | Representing Bayer AGSearch in Eureka ↗ |
| Plaintiff law firm | Williams & Connolly LLP – Washington | Law Firm | Representing Bayer AGSearch in Eureka ↗ |
| Defendant counsel | David Ellis Moore | Attorney | Counsel for Mylan, NVSearch in Eureka ↗ |
| Defendant counsel | Gordon H. Copland | Attorney | Counsel for Mylan, NVSearch in Eureka ↗ |
| Defendant counsel | Ty W. Callahan | Attorney | Counsel for Mylan, NVSearch in Eureka ↗ |
| Defendant counsel | Wendy L. Devine | Attorney | Counsel for Mylan, NVSearch in Eureka ↗ |
| Defendant counsel | William J. O’Brien | Attorney | Counsel for Mylan, NVSearch in Eureka ↗ |
| Defendant law firm | Potter Anderson & Corroon, LLP | Law Firm | Representing Mylan, NVSearch in Eureka ↗ |
| Defendant law firm | Steptoe & Johnson PLLC – Bridgeport | Law Firm | Representing Mylan, NVSearch in Eureka ↗ |
| Presiding judge | Judge Richard G. Andrews | Judge | Delaware District CourtSearch in Eureka ↗ |
Official order — verbatim text
The stipulation expressly invokes FRCP 41(a)(1) and 41(c), covering both the plaintiffs’ affirmative infringement claims and Mylan’s counterclaims respectively. The with-prejudice designation is significant: it functions as a final judgment on the merits, permanently barring re-litigation of every claim and defence raised in this action. The mutual own-costs provision is consistent with a negotiated resolution in which both parties made concessions — the public record does not disclose what, if any, commercial terms accompanied the dismissal.
US10828310B2 — 2.5 mg rivaroxaban oral anticoagulant tablet formulation
US10828310B2, filed under application number US16/264032, covers formulations of rivaroxaban — a direct oral anticoagulant (DOAC) — specifically at the 2.5 mg dose marketed as XARELTO®. This dose is clinically distinct from higher-strength rivaroxaban formulations: it is approved for reducing the risk of cardiovascular events in patients with coronary artery disease or peripheral arterial disease, often in combination with aspirin. The patent’s coverage of this specific low-dose formulation gives it particular commercial relevance in the cardiovascular indication segment.
XARELTO® is one of the world’s highest-revenue pharmaceutical products, and the 2.5 mg dose occupies a strategically important cardiovascular niche. A patent covering this specific formulation creates a meaningful barrier to generic entry at a dose that commands its own market segment, separate from the anticoagulation indications addressed by higher-strength rivaroxaban. For generic manufacturers, any ANDA for 2.5 mg rivaroxaban tablets must contend with this patent before FDA approval can translate to commercial launch — making US10828310B2 a gating asset in the XARELTO® lifecycle management portfolio.
Should you run an FTO against US10828310B2 before launching 2.5 mg rivaroxaban?
Any pharmaceutical company with an ANDA, 505(b)(2), or biosimilar-adjacent product incorporating 2.5 mg rivaroxaban tablet formulations should treat US10828310B2 as a live enforcement risk. The patent survived this Delaware litigation without a validity ruling, and Bayer and Janssen retain full enforcement rights. With-prejudice dismissal of Mylan’s specific counterclaims does not create any estoppel benefit for third-party filers — each new ANDA applicant faces the patent fresh.
PatSnap Eureka’s FTO Search Agent can map the full claim scope of US10828310B2 against your formulation parameters, surface related continuation and divisional applications in the XARELTO® portfolio, and identify prior art landscapes that informed or constrained the granted claims. Eureka’s prosecution history analysis tools allow R&D teams to understand claim amendments made during prosecution — critical intelligence before designing around a formulation patent in a regulated pharmaceutical context.
Run a freedom-to-operate analysis on US10828310B2 to assess your product’s exposure
Run FTO in Eureka →Similar ANDA rivaroxaban patent disputes in Delaware District Court
Explore comparable ANDA pharmaceutical patent infringement cases involving rivaroxaban and DOAC formulations litigated in the Delaware District Court.
What this case signals for the pharmaceutical anticoagulant IP landscape
A three-year ANDA dispute ending by mutual stipulation points to negotiated market access — not patent weakness — as the operative dynamic.
US10828310B2 exits litigation with validity intact — enforce-ability risk low
Because the court issued no validity or infringement ruling, US10828310B2 retains its full presumption of validity. Bayer and Janssen face no weakened patent position heading into potential disputes with other generic filers. Companies with pending ANDAs for 2.5 mg rivaroxaban products should treat this patent as an active enforcement risk.
Own-costs clause suggests rough parity in litigation leverage
When pharmaceutical patent disputes settle with each side bearing its own fees, it typically signals that neither party held a dominant position at the time of resolution. The 1,184-day timeline suggests substantive motions practice occurred before resolution, meaning Mylan likely extracted concessions beyond a simple walk-away despite the with-prejudice designation.
Bayer v Mylan — key questions answered
A dismissal with prejudice is a final, merits-equivalent termination. Under FRCP 41(a)(1) and 41(c), both Bayer/Janssen’s infringement claims and Mylan’s counterclaims are permanently extinguished. Neither party may refile the same claims in a new action. The court issued no ruling on patent validity or infringement.
The plaintiffs asserted US10828310B2 (application number US16/264032), covering 2.5 mg rivaroxaban tablet formulations sold under the brand name XARELTO®. The 2.5 mg dose is specifically approved for cardiovascular risk reduction in patients with coronary artery disease or peripheral arterial disease.
Yes. Because the court issued no invalidity or unenforceability ruling, US10828310B2 retains its statutory presumption of validity. Bayer and Janssen can assert it against other generic filers. The with-prejudice dismissal creates no estoppel benefit for third parties who were not party to this action.
The own-costs provision was agreed by stipulation, suggesting a negotiated resolution in which neither side claimed a clear litigation win. In ANDA patent cases, mutual own-costs arrangements are common when parties reach a commercial accommodation — such as an authorised-generic agreement or a negotiated market-entry date — before trial.
The case lasted 1,184 days — approximately 3.2 years — from filing in September 2022 to dismissal in December 2025. This duration is consistent with contested ANDA pharmaceutical patent litigation in Delaware, which routinely involves claim construction, expert discovery, and extensive motion practice before resolution. The stipulated end suggests a commercial resolution was reached before any trial date.
PatSnap Eureka searches patents and litigation data to answer instantly.