Bayer AG & Monsanto v. Pierce: Biotech Seed Patent Suit Dismissed With Prejudice
Bayer AG and Monsanto Technology LLC brought a patent infringement action against Robert O. Pierce Jr. in Missouri’s Eastern District Court, asserting two agricultural biotechnology patents covering herbicide-tolerance mechanisms and a proprietary soybean event. After 469 days of litigation, the plaintiffs voluntarily dismissed the case with prejudice under Rule 41(a)(1)(A)(ii).
A Monsanto Seed-Patent Enforcement Action That Ended Conclusively
Filed on 25 January 2023 in the Eastern District of Missouri before Judge John A. Ross, this infringement action was brought by Bayer AG and its subsidiary Monsanto Technology LLC against a single individual defendant, Robert O. Pierce Jr. The two patents asserted — US7838729B2, covering chloroplast transit peptides for efficient DMO targeting, and US9944945B2, covering soybean event MON89788 and detection methods — sit at the heart of Monsanto’s herbicide-tolerance and seed-trait licensing program.
The case closed on 8 May 2024 when plaintiffs filed a stipulated voluntary dismissal with prejudice pursuant to Federal Rule of Civil Procedure 41(a)(1)(A)(ii). Dismissal with prejudice is legally final: the plaintiffs are permanently barred from refiling the same claims against Pierce on these two patents. The mechanism — Rule 41(a)(1)(A)(ii) — requires the opposing party’s agreement or a court-approved stipulation, suggesting some form of negotiated resolution preceded the filing, though no settlement terms are disclosed in the public record.
The 469-day duration before a with-prejudice dismissal is notable for a case involving a single individual defendant; it suggests the parties may have engaged in substantive negotiations, discovery, or reached a private agreement before closing the litigation. The precise terms — including any licensing arrangement, payment, or conduct undertaking — remain confidential. What is clear is that Pierce faces no ongoing judicial exposure on these specific patent claims.
Filing to Voluntary dismissal in 469 days
469 days — longer than the median voluntary dismissal in district-level ag-biotech cases
Voluntary dismissal with prejudice: what closing on these terms means for both sides
Rule 41(a)(1)(A)(ii) dismissal with prejudice is final and non-refundable
Under FRCP 41(a)(1)(A)(ii), a plaintiff may voluntarily dismiss an action without a court order when all parties who have appeared agree. Adding ‘with prejudice’ converts what would be a neutral exit into a permanent bar: Bayer and Monsanto cannot re-assert US7838729B2 or US9944945B2 against Pierce on the same facts. This is a stronger concession than a simple voluntary dismissal and typically signals a negotiated resolution.
Permanent bar on refilingBayer and Monsanto permanently close the door on this defendant
Dismissing with prejudice forfeits the right to pursue Pierce again on these patents. While plaintiffs give up litigation leverage, they likely secured something in return — whether a licensing arrangement, a grower agreement, or a conduct commitment. The public record is silent on specific terms. From an enforcement-portfolio perspective, the case is resolved cleanly with no outstanding judicial risk.
Claims extinguished against PiercePierce is permanently released from these two patent claims
With prejudice dismissal is the strongest form of closure a defendant can achieve short of a court judgment in their favour. Robert O. Pierce Jr. faces no further liability to Bayer or Monsanto under US7838729B2 or US9944945B2 for the conduct alleged. Whether Pierce agreed to change his farming or seed-saving practices as part of any private arrangement is not reflected in the public docket.
No remaining judicial exposureIndividual grower enforcement: patent holders close cases quietly but decisively
Monsanto and Bayer have a well-documented history of enforcing seed-technology patents against individual growers. Cases resolved with prejudice after extended negotiation suggest that the enforcement program operates as much through deterrence and private settlement as through judgments. Other growers or seed dealers working with DMO-tolerant soy varieties should treat these patents as actively monitored and enforcement-ready assets.
Active seed-patent enforcement programFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Bayer AG | Company | Agricultural biotech and crop-science conglomerate — holders of US7838729B2 and US9944945B2Search in Eureka ↗ |
| Co-Plaintiff | Monsanto Technology, LLC | Company | Search in Eureka ↗ |
| Defendant | Robert O. Pierce, Jr. | Individual | Individual defendant Robert O. Pierce Jr., represented by Hoskins Law OfficeSearch in Eureka ↗ |
| Plaintiff counsel | Anthony F. Blum | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff counsel | Daniel C. Cox | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff counsel | Jeffrey A. Masson | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff counsel | Matthew S. Bober | Attorney | Counsel for Bayer AGSearch in Eureka ↗ |
| Plaintiff law firm | Thompson Coburn LLP (St Louis) | Law Firm | Representing Bayer AGSearch in Eureka ↗ |
| Defendant counsel | Wendell L. Hoskins , II | Attorney | Counsel for Robert O. Pierce, Jr.Search in Eureka ↗ |
| Defendant law firm | Hoskins Law Office | Law Firm | Representing Robert O. Pierce, Jr.Search in Eureka ↗ |
| Presiding judge | Judge John A. Ross | Judge | Missouri Eastern District CourtSearch in Eureka ↗ |
Official order — verbatim text
The dismissal notice records plaintiffs as ‘Monsanto Company and Bayer CropScience LP’ — slightly different entity names from the case caption — which is not uncommon in corporate-family litigation where operating and holding entities differ. The with-prejudice qualifier is legally dispositive: it eliminates any future claim on the same facts. Rule 41(a)(1)(A)(ii) requires opposing-party agreement, indicating Pierce’s counsel consented, which is consistent with a negotiated exit rather than a unilateral withdrawal.
US7838729B2 & US9944945B2 — Herbicide Tolerance and Soybean Event Patents
US7838729B2 claims chloroplast transit peptide sequences that shuttle the dicamba mono-oxygenase (DMO) enzyme into the chloroplast of transgenic plants, enabling herbicide tolerance. Filed under application US11/758659, this patent covers a foundational molecular mechanism used in herbicide-tolerance trait stacks. US9944945B2, filed as US14/539923, protects the specific soybean transformation event MON89788 — commercially known as Roundup Ready 2 Yield — and the diagnostic methods for detecting its presence in plant material, grain, and processed products.
Together, these patents represent two layers of Monsanto’s herbicide-tolerance IP fortress: one covering the delivery mechanism for the tolerance protein, the other covering the specific commercial event. Both patents remain material to Bayer’s crop-science licensing program. US9944945B2’s detection-method claims are particularly strategically significant because they can reach entities far downstream from the grower — including grain handlers, processors, and exporters — wherever MON89788 presence must be confirmed or declared.
Should your R&D team run an FTO against US7838729B2 and US9944945B2?
Any team developing herbicide-tolerant soybean events, dicamba-tolerant crop traits, or chloroplast-targeted protein delivery systems should assess freedom-to-operate against US7838729B2 before advancing to field trials. Similarly, seed companies, trait licensors, grain processors, and exporters handling soybean varieties derived from or related to the MON89788 event need to evaluate US9944945B2’s detection-method claims. This case confirms both patents are being actively enforced.
PatSnap Eureka’s FTO Search Agent can map your trait-delivery sequences and event-detection protocols against the claim scope of US7838729B2 and US9944945B2, surface design-around opportunities, and identify prior art relevant to validity challenges. Eureka’s litigation monitoring layer also flags new enforcement actions involving these patents so your IP team stays ahead of emerging risk.
Run a freedom-to-operate analysis on US7838729B2 to assess your product’s exposure
Run FTO in Eureka →Similar Ag-Biotech Seed Patent Enforcement Cases in Federal District Courts
Cases involving Monsanto and Bayer seed-technology patents litigated in Missouri and other federal district courts, including MON89788 and herbicide-tolerance trait disputes.
What this case signals for the agricultural biotech IP landscape
Monsanto’s seed-patent enforcement model targets individuals as well as companies. This case confirms the program remains active.
Individual growers remain in scope for Bayer/Monsanto patent enforcement
This case against a single individual defendant confirms that Bayer and Monsanto’s enforcement program is not limited to commercial competitors. Agribusinesses, seed dealers, and growers using herbicide-tolerant soybean varieties linked to DMO or MON89788 events should conduct FTO analysis and review seed agreements proactively.
With-prejudice closure after 469 days typically reflects private resolution
The combination of an extended pre-closure period and a with-prejudice stipulation is consistent with a negotiated resolution — potentially including a licensing fee, a grower agreement, or both. Companies monitoring Bayer/Monsanto enforcement activity should note this pattern: cases do not need to reach judgment to produce commercially binding outcomes.
Bayer v Robert — key questions answered
Bayer AG and Monsanto Technology LLC asserted US7838729B2 (chloroplast transit peptides for DMO targeting) and US9944945B2 (soybean event MON89788 and detection methods) against Robert O. Pierce Jr. in the Eastern District of Missouri.
The plaintiffs filed a stipulated voluntary dismissal with prejudice under FRCP 41(a)(1)(A)(ii). This requires the agreement of all parties who have appeared and permanently bars the plaintiffs from refiling the same claims. The precise reason — whether a settlement, licensing agreement, or other resolution — is not disclosed in the public record.
Pierce is permanently released from liability to Bayer and Monsanto under US7838729B2 and US9944945B2 for the conduct alleged in this action. The plaintiffs cannot refile these patent claims against him. Any private undertaking Pierce may have given as part of a negotiated resolution is not reflected in the public docket.
MON89788, marketed as Roundup Ready 2 Yield, is a specific transgenic soybean transformation event developed by Monsanto. US9944945B2 protects both the event itself and the molecular detection methods used to confirm its presence in plant material and grain. These detection claims extend potential infringement exposure beyond growers to processors and exporters.
US7838729B2 covers the molecular sequences that direct the dicamba mono-oxygenase (DMO) enzyme into the chloroplast of transgenic plants, enabling dicamba herbicide tolerance. This mechanism is foundational to herbicide-tolerance trait stacks. R&D teams developing new tolerance events using similar transit peptide strategies should conduct FTO analysis against this patent’s claims.
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