Epson vs. Weston Tees: Consent Judgment & Permanent Injunction in Ink Cartridge Patent Case
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In a swift resolution that reinforces Epson’s aggressive posture in protecting its printer consumables portfolio, Seiko Epson Corporation secured a stipulated consent judgment and permanent injunction against Texas-based Weston Tees LLC in just 154 days. Filed in the Northern District of Texas on October 18, 2023, and closed on March 20, 2024, case 3:23-cv-02303 centered on two foundational Epson ink cartridge patents and a line of third-party replacement cartridges sold into the U.S. market.
For patent attorneys, IP professionals, and R&D teams operating in the printing technology space, this case offers a textbook example of how a dominant OEM uses strategic patent assertion to shut down aftermarket competitors efficiently — without protracted litigation. The outcome underscores that ink cartridge patent infringement remains a high-enforcement priority for Epson, and that small-to-midsize resellers face substantial legal exposure when their product lines intersect with entrenched OEM patent portfolios.
📋 Case Summary
| Case Name | Seiko Epson Corporation v. Weston Tees LLC |
| Case Number | 3:23-cv-02303 (N.D. Tex.) |
| Court | United States District Court for the Northern District of Texas |
| Duration | Oct 2023 – Mar 2024 154 days |
| Outcome | Plaintiff Win — Permanent Injunction |
| Patents at Issue | |
| Accused Products | Third-party ink cartridges for Epson printers (e.g., Epson Model No. T7251, T725200, etc.) |
Case Overview
The Parties
⚖️ Plaintiffs
Japan-based parent company and patent owner. Included Epson America, Inc. (U.S. distribution licensee) and Epson Portland, Inc. (U.S. manufacturing licensee).
🛡️ Defendants
Texas corporation engaged in the sale of ink cartridges in the United States. Also included individual defendants Devon Walden and Weston Griffin.
Patents at Issue
Two U.S. patents formed the legal foundation of Epson’s claims, covering core technical architecture in Epson’s cartridge ecosystem — fundamental IP creating broad downstream infringement risk for aftermarket parties. Design patents are registered with the U.S. Patent and Trademark Office (USPTO).
- • U.S. Patent No. 8,794,749 (App. No. 13/902,171) — issued August 5, 2014, covering ink cartridges, circuit boards for ink cartridges, and printing material containers.
- • U.S. Patent No. 8,454,116 (App. No. 13/608,658) — issued June 4, 2013, covering ink-supply systems for printers and components thereof.
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The Verdict & Legal Analysis
Litigation Timeline & Procedural History
| Complaint Filed | October 18, 2023 |
| Consent Judgment Entered | March 20, 2024 |
| Total Duration | 154 days |
The case was filed in the United States District Court for the Northern District of Texas, presided over by Chief Judge Karen Gren Scholer. The 154-day resolution is notably fast for patent infringement litigation, suggesting the defendant recognized the strength of Epson’s patent position.
Outcome
The case concluded with a Stipulated Final Consent Judgment and Permanent Injunction, entered by Chief Judge Karen Gren Scholer on March 20, 2024. Weston Tees LLC is permanently enjoined from selling, offering for sale, or distributing in the United States the accused ink cartridge products that infringe the ‘749 and ‘116 patents.
Key Legal Issues
The action was an infringement action — no counterclaims of invalidity or unenforceability were litigated to conclusion. The consent judgment stipulates that Weston Tees had sold and offered for sale within the United States, including Texas, ink cartridges for use with Epson printers that Epson alleged infringed its patents. The strategic calculus for Weston Tees is straightforward: contesting both patents against K&L Gates and Quinn Emanuel would have required substantial litigation investment with low probability of success.
While consent judgments carry limited precedential value for claim construction or validity doctrine, this case carries important strategic signal value:
- Epson’s dual-patent assertion strategy creates redundant claim coverage that complicates invalidity challenges.
- The use of three plaintiff entities establishes comprehensive standing and eliminates procedural defenses.
- The permanent injunction, rather than a royalty-bearing license, signals that Epson’s IP enforcement priority is market exclusion.
Freedom to Operate (FTO) Analysis
This case highlights critical IP risks in the aftermarket printer consumables. Choose your next step:
📋 Understand This Case’s Impact
Learn about the specific risks and implications from this litigation.
- View all related patents in this technology space
- See which companies are most active in ink cartridge patents
- Understand claim construction patterns
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High Risk Area
Ink cartridge chip and circuit board architecture
Key OEM Patents
Foundational IP in printer consumables
Strategic Design-Arounds
Possible with careful analysis
✅ Key Takeaways
Multi-entity plaintiff structures (OEM + licensees) strengthen standing and signal enforcement commitment.
Search related case law →Consent judgments with permanent injunctions can be more strategically valuable than damages awards for market-protective enforcement.
Explore precedents →The 154-day resolution demonstrates that rapid, pre-discovery resolution is achievable when resource asymmetry is pronounced.
Analyze litigation timelines →Monitor Epson’s growing assertion activity in the Northern District of Texas as a venue signal for future ink cartridge patent cases.
Track litigation trends →Aftermarket consumable supply chains require proactive FTO clearance at the reseller level, not just the manufacturer level.
Conduct FTO for my product →Frequently Asked Questions
The case involved U.S. Patent No. 8,794,749 (issued August 5, 2014) and U.S. Patent No. 8,454,116 (issued June 4, 2013), both relating to ink cartridge systems, circuit boards, and ink-supply systems for Epson printers.
The case was resolved through a Stipulated Final Consent Judgment and Permanent Injunction, entered March 20, 2024. Weston Tees LLC agreed to the judgment without contesting infringement, resulting in a permanent injunction against further sales of the accused cartridge products.
It reinforces that OEM patent holders like Epson will pursue permanent injunctive relief — not just damages — against aftermarket resellers, and that resellers at any scale face real legal risk without thorough FTO clearance.
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References
- PACER Case Lookup – 3:23-cv-02303 (Northern District of Texas)
- Northern District of Texas Court Information
- USPTO Patent Center – U.S. Patent No. 8,794,749
- USPTO Patent Center – U.S. Patent No. 8,454,116
- PatSnap — IP Intelligence Solutions for Law Firms
This article is for informational purposes only and does not constitute legal advice. All case information is drawn from publicly available court records. For platform capabilities, visit PatSnap.