Yuyao Tanghong v. Fohse: LED Grow Light Patent Settled After 678 Days
Yuyao Tanghong International Trade Co. brought a patent infringement action against Fohse, Inc. in Nevada federal court, asserting US10638670B2 against Fohse’s A3i, F1V, Aries, and Scorpio series of industrial horticultural LED grow lights. The parties reached a confidential settlement after 678 days, dismissing the case with prejudice.
A contested LED grow light IP dispute ends in confidential settlement
On 2 November 2023, Yuyao Tanghong International Trade Co., Ltd., a Chinese international trade company, filed a patent infringement action against Fohse, Inc. in the U.S. District Court for the District of Nevada. The complaint centred on US10638670B2, a patent covering industrial horticultural LED grow light technology, which Tanghong alleged was infringed by Fohse’s premium A3i, F1V, Aries, and Scorpio product lines — fixtures sold specifically into the high-intensity commercial cannabis cultivation market.
The case closed on 10 September 2025 following a confidential private settlement. The parties filed a stipulated dismissal with prejudice, meaning neither side may re-litigate the same claims. Because the settlement terms are sealed, the public record does not disclose any royalty, licence, damages payment, or product design change. A with-prejudice dismissal is legally final and bars future assertion of the same claims against Fohse on the same basis.
The 678-day duration suggests the parties engaged in substantive litigation activity — including likely claim construction and discovery — before arriving at terms. The decision to resolve confidentially is consistent with commercial patent disputes where reputational exposure, licensing economics, or supply-chain continuity outweigh the value of a public adjudication. What drove the specific settlement terms, including whether any ongoing licence was granted, remains unknown from the public record.
Filing to Case Settled in 678 days
678 days — above average for a district court patent case settling before trial
Dismissed with prejudice: what the confidential settlement means for both parties
Stipulated dismissal with prejudice: the case is permanently closed
A dismissal with prejudice under Federal Rule of Civil Procedure 41(a) is a final adjudication on the merits for procedural purposes. Yuyao Tanghong cannot bring the same patent infringement claims under US10638670B2 against Fohse again in any federal court. The stipulated nature — agreed by both parties — typically signals a negotiated resolution rather than a unilateral concession by either side.
Permanent bar on re-filingPrivate terms sealed: licence, damages, and product changes undisclosed
The parties characterised the agreement as a ‘private, confidential settlement.’ The public record does not reveal whether Fohse paid a lump-sum damages award, entered a running royalty licence, agreed to design modifications, or received a covenant not to sue. This opacity is commercially deliberate — it prevents competitors from using settlement value as a pricing benchmark for the same patent in future disputes.
Terms not in public recordTanghong secures finality — but enforceability signal is mixed
A with-prejudice dismissal forecloses future action against Fohse, which may indicate Tanghong secured sufficient commercial value — whether monetary or licensing — to justify that concession. However, because no court adjudicated the validity or scope of US10638670B2, the patent’s enforceability against other market participants remains an open question. Tanghong retains the right to assert the patent against third parties.
Patent validity untestedFohse’s flagship grow lights cleared — but uncertainty persists for the sector
Fohse’s A3i, F1V, Aries, and Scorpio product lines continue to market without any published consent decree or injunction on record. Other LED grow light manufacturers cannot determine from this outcome whether US10638670B2 poses a genuine infringement risk to their own products. The absence of a claim construction order or validity ruling means the patent’s effective scope remains untested, maintaining assertion risk across the commercial horticulture lighting sector.
Sector uncertainty persistsFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Yuyao Tanghong International Trade Co., Ltd. | Company | International trade company — holder of US10638670B2, horticultural LED grow lightsSearch in Eureka ↗ |
| Defendant | Fohse, Inc. | Company | Fohse, Inc. — U.S.-based manufacturer of high-intensity LED fixtures for commercial horticultureSearch in Eureka ↗ |
| Plaintiff counsel | Emily Marie Heim | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff counsel | Gokalp Bayramoglu | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff counsel | Hao Ni | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff counsel | Joanna Myers | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff counsel | Jonathan W. Fountain | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff counsel | Nihat Deniz Bayramoglu | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff counsel | Shawn Anthony Mangano | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff counsel | William Robert Brees | Attorney | Counsel for Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff law firm | Bayramoglu Law Offices LLC | Law Firm | Representing Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff law firm | Gokalp Bayramoglu | Law Firm | Representing Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff law firm | Howard & Howard Attorneys PLLC | Law Firm | Representing Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff law firm | Howard & Howard PLLC | Law Firm | Representing Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff law firm | Ni, Wang & Massand, PLLC | Law Firm | Representing Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Plaintiff law firm | Wilson Elser Moskowitz Edelman & Dicker LLP | Law Firm | Representing Yuyao Tanghong International Trade Co., Ltd.Search in Eureka ↗ |
| Defendant counsel | F. Christopher Austin | Attorney | Counsel for Fohse, Inc.Search in Eureka ↗ |
| Defendant counsel | Henry Jared Doster | Attorney | Counsel for Fohse, Inc.Search in Eureka ↗ |
| Defendant counsel | R. Scott Weide | Attorney | Counsel for Fohse, Inc.Search in Eureka ↗ |
| Defendant law firm | Lex Tecnica, Ltd. | Law Firm | Representing Fohse, Inc.Search in Eureka ↗ |
| Defendant law firm | Snell & Wilmer LLP | Law Firm | Representing Fohse, Inc.Search in Eureka ↗ |
| Presiding judge | Judge N/A | Judge | Nevada District CourtSearch in Eureka ↗ |
Official order — verbatim text
The stipulated dismissal language — ‘having reached a private, confidential settlement agreement’ — confirms the resolution was consensual and commercially negotiated rather than adjudicated. The with-prejudice designation is the critical legal qualifier: it renders the dismissal equivalent to a final judgment for claim-preclusion purposes, permanently extinguishing Tanghong’s infringement claims against Fohse under this patent. No findings of fact, claim construction, or validity ruling accompany the dismissal, leaving the patent’s scope and validity legally untested.
US10638670B2 — Industrial Horticultural LED Grow Light Technology
US10638670B2 (application no. US16/411054) is a U.S. utility patent covering industrial horticultural LED grow light technology. The patent addresses the design and configuration of high-intensity LED fixtures engineered for controlled-environment agriculture, including commercial cannabis cultivation. Patents in this category typically protect thermal management, spectral output configurations, driver circuitry, and fixture housing geometry — the specific claims of US10638670B2 were not adjudicated in this proceeding, so their precise scope remains undefined by any court ruling.
The commercial significance of this patent lies in its applicability to the premium end of the horticultural lighting market, where products like Fohse’s A3i and Scorpio series command high price points and serve large-scale cultivation facilities. Any manufacturer competing in the high-intensity LED segment — particularly those targeting cannabis, vertical farming, or greenhouse operations — faces potential exposure if their product architecture overlaps with this patent’s claims. The absence of any invalidity finding means US10638670B2 continues to carry a presumption of validity under 35 U.S.C. § 282.
Should your team run an FTO against US10638670B2?
Any company designing, importing, or selling high-intensity horticultural LED grow light fixtures in the U.S. market should treat US10638670B2 as an active FTO priority. The patent was asserted against a leading commercial grow light manufacturer, the case resolved without any claim construction or invalidity ruling, and the patent holder retains full rights to assert against third parties. Product teams launching new fixtures — particularly those with LED array configurations, thermal management systems, or spectral control features — face the most direct exposure.
PatSnap Eureka’s FTO Search Agent enables R&D and IP teams to map their product specifications against the claim language of US10638670B2, identify design-around opportunities, and surface prior art that could support an invalidity argument if assertion occurs. Eureka also monitors litigation activity citing this patent in real time, alerting teams to new enforcement filings before they reach the discovery phase.
Run a freedom-to-operate analysis on US10638670B2 to assess your product’s exposure
Run FTO in Eureka →Similar Horticultural LED Patent Infringement Cases in U.S. District Courts
Explore comparable LED grow light and horticultural lighting patent disputes filed in U.S. district courts, including similar infringement and settlement patterns.
What this case signals for the horticultural LED lighting IP landscape
A settled, sealed dispute over grow light patents leaves key questions open for competitors and product developers in the commercial horticulture sector.
US10638670B2 remains a live threat to other LED grow light makers
Because no court ruled on validity or claim scope, US10638670B2 retains full enforcement potential against competitors. Manufacturers of high-intensity horticultural LED fixtures — particularly those targeting the cannabis cultivation market — should conduct a formal FTO review before expanding product lines that overlap with this patent’s claims.
Settlement before trial means claim construction was never locked in
Without a Markman ruling, the exact boundaries of US10638670B2’s claims are undefined in the public record. This is commercially significant: other defendants facing assertion of this patent cannot rely on prior judicial narrowing. Each potential defendant would need to litigate claim scope afresh or negotiate independently.
Yuyao v Fohse — key questions answered
The case was dismissed with prejudice on 10 September 2025 following a confidential private settlement. The settlement terms, including any financial consideration or licensing arrangement, are not disclosed in the public record. The with-prejudice dismissal bars Yuyao Tanghong from re-asserting the same claims under US10638670B2 against Fohse.
Yuyao Tanghong asserted US10638670B2 (application no. US16/411054), a patent covering industrial horticultural LED grow light technology. The patent was alleged to be infringed by Fohse’s A3i, F1V, Aries, and Scorpio series LED grow light products, which are targeted at commercial horticulture including large-scale cannabis cultivation.
No. The case settled before any court ruling on validity or claim construction. US10638670B2 retains its presumption of validity under 35 U.S.C. § 282 and remains enforceable against third parties. The settlement does not constitute any judicial finding regarding the patent’s scope or validity, and cannot be relied upon as precedent by other potential defendants.
A dismissal with prejudice is a final termination of the litigation. It functions as a judgment on the merits for claim-preclusion purposes, meaning the plaintiff cannot re-file the same claims against the same defendant in any federal court. In the context of a patent settlement, it typically signals that the parties reached a commercially satisfactory resolution and agreed to permanently end the dispute.
The District of Nevada is a natural venue for claims against Fohse, Inc., which is based in Nevada. Under 28 U.S.C. § 1400(b), patent cases may be brought where the defendant resides or has a regular place of business. Filing in the defendant’s home district is a common plaintiff strategy to reduce jurisdictional challenges and establish a credible forum for early resolution.
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