Katana Silicon v. Micron Technology: Federal Circuit Affirms Unpatentability
Katana Silicon Technologies, LLC appealed a patentability ruling against US6352879B1, a semiconductor device and manufacturing method patent, with Micron Technology, Inc. as respondent. The Federal Circuit affirmed the unpatentability finding after 643 days of appellate proceedings.
Federal Circuit seals semiconductor patent defeat for Katana Silicon
Katana Silicon Technologies, LLC brought this appeal before the United States Court of Appeals for the Federal Circuit (Case No. 24-2103), filed on 17 July 2024, challenging an underlying invalidity or cancellation determination against US6352879B1. The patent covers a semiconductor device and method of manufacturing the same. Micron Technology, Inc., one of the world's leading DRAM and NAND flash memory manufacturers, was the respondent.
The Federal Circuit issued its order on 21 April 2026, affirming the lower tribunal's ruling. The court's order states: 'THIS CAUSE having been considered, it is ORDERED AND ADJUDGED: AFFIRMED.' The recorded basis of termination is 'Unpatentable,' confirming that US6352879B1 has been found unpatentable and that finding now stands as a final appellate determination.
The 643-day appellate duration is consistent with complex patent validity appeals before the Federal Circuit. The affirmance forecloses further challenge to the patent's validity at this level, and the specific grounds on which the lower tribunal found unpatentability, as well as any licensing or commercial arrangements between the parties, are not disclosed in the available record.
See Complete Case & Patent Analysis →Filing to Unpatentable in 643 days
643 days from filing to Federal Circuit decision — a substantial appellate timeline
US6352879B1 — Semiconductor Device and Method of Manufacturing
US6352879B1 has been determined unpatentable and that finding affirmed by the Federal Circuit, which significantly reduces — but does not necessarily eliminate — the practical need for a freedom-to-operate analysis in all contexts. R&D and product teams developing semiconductor devices or manufacturing processes should still assess related patents in the same family or from the same assignee, as those assets may not share the same legal fate.
Official order — verbatim text
The Federal Circuit's order — 'THIS CAUSE having been considered, it is ORDERED AND ADJUDGED: AFFIRMED' — is a merits affirmance of the unpatentability determination below, consistent with the recorded basis of termination. The court applied its standard appellate review, finding no reversible legal error in the lower tribunal's invalidity or cancellation ruling. The specific grounds of unpatentability upheld are not detailed in the order text available in the record.
Federal Circuit affirms: what the ruling means for both parties
What 'AFFIRMED' means at the Federal Circuit
An affirmance by the Federal Circuit means the appellate panel reviewed the lower tribunal's unpatentability determination and found no reversible error in law or fact. The lower ruling is left fully intact. For patent validity challenges, affirmance signals that the appellate court was satisfied the record supported the unpatentability conclusion under the applicable standard of review.
No reversible error foundUS6352879B1 is now unpatentable — enforcement options exhausted
For Katana Silicon Technologies, the affirmance is a final adverse ruling. US6352879B1 has been determined unpatentable, and that determination is now affirmed at the highest available appellate level short of the Supreme Court. The patent cannot be enforced as valid, and any pending or planned licensing or litigation strategy built around this patent is materially compromised.
Patent unenforceable as validMicron secures appellate confirmation of invalidity
Micron Technology emerges from this appeal with the unpatentability finding confirmed. The affirmance removes the threat of US6352879B1 being reasserted against Micron's semiconductor manufacturing operations. Competitors and licensees who may have faced exposure under this patent also benefit from the binding appellate ruling establishing unpatentability.
Invalidity confirmed on appealSemiconductor manufacturing method patent eliminated from the landscape
The Federal Circuit's affirmance clears US6352879B1 from the semiconductor device and manufacturing IP landscape. For R&D teams and product engineers working in this technology domain, the ruling reduces the assertion risk associated with this specific patent. However, Katana Silicon or related entities may hold further portfolio assets, and practitioners should monitor for related filings in the semiconductor manufacturing space.
Reduced assertion risk for sectorFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Katana Silicon Technologies, LLC | Company | /Search in Eureka ↗ |
| Defendant | Micron Technology, Inc. | Company | /Search in Eureka ↗ |
| Plaintiff counsel | Alexis Leia Ritzer | Attorney | Counsel for Katana Silicon Technologies, LLCSearch in Eureka ↗ |
| Plaintiff counsel | Howard Lithaw Lim | Attorney | Counsel for Katana Silicon Technologies, LLCSearch in Eureka ↗ |
| Plaintiff counsel | Michael Clayton Pomeroy | Attorney | Counsel for Katana Silicon Technologies, LLCSearch in Eureka ↗ |
| Plaintiff counsel | Scott W. Breedlove | Attorney | Counsel for Katana Silicon Technologies, LLCSearch in Eureka ↗ |
| Plaintiff law firm | Carter Arnett PLLC | Law Firm | Representing Katana Silicon Technologies, LLCSearch in Eureka ↗ |
| Plaintiff law firm | Cozen O'connor PC | Law Firm | Representing Katana Silicon Technologies, LLCSearch in Eureka ↗ |
| Plaintiff law firm | Gardella Alciati PA | Law Firm | Representing Katana Silicon Technologies, LLCSearch in Eureka ↗ |
| Defendant counsel | Amanda Tessar | Attorney | Counsel for Micron Technology, Inc.Search in Eureka ↗ |
| Defendant counsel | Amy Elizabeth Simpson | Attorney | Counsel for Micron Technology, Inc.Search in Eureka ↗ |
| Defendant counsel | Andrew Dufresne | Attorney | Counsel for Micron Technology, Inc.Search in Eureka ↗ |
| Defendant law firm | Holland & Knight LLP | Law Firm | Representing Micron Technology, Inc.Search in Eureka ↗ |
| Defendant law firm | Perkins Coie LLP | Law Firm | Representing Micron Technology, Inc.Search in Eureka ↗ |
| Presiding judge | Judge N/A | Judge | Court of Appeals for the Federal CircuitSearch in Eureka ↗ |
R&D signals in the semiconductor device patent space
Forward-looking patent and innovation intelligence derived from the Katana Silicon v. Micron Technology Federal Circuit appeal and the semiconductor manufacturing IP landscape.
Katana Silicon's semiconductor patent footprint beyond US6352879
With US6352879B1 now unpatentable, understanding the breadth and status of Katana Silicon Technologies' broader semiconductor portfolio is critical for any manufacturer in this space. Active continuations, divisionals, or related applications from the same family may still present assertion risk. A portfolio map of Katana Silicon's filings can reveal whether additional live patents cover overlapping semiconductor device or process technology.
Portfolio monitoringFiling trends in semiconductor device manufacturing method patents
The semiconductor device and manufacturing method patent space continues to see active filing activity from integrated device manufacturers, foundries, and IP assertion entities. Understanding filing trends around semiconductor process patents — particularly those claiming structural or process innovations similar to US6352879B1 — helps R&D teams anticipate where future assertion risk may concentrate and where white space exists for novel filings.
Technology filing trendsMicron Technology's defensive and offensive semiconductor IP position
Micron Technology's successful Federal Circuit defence of this unpatentability finding reflects a mature and well-resourced patent litigation capability. Examining Micron's own semiconductor device and manufacturing patent portfolio can reveal areas of active R&D investment, potential licensing leverage points, and technology domains where Micron is building defensive IP density relevant to future disputes.
Micron IP landscapeAdjacent innovation opportunities in semiconductor device manufacturing
The invalidation of US6352879B1 opens a small window of reduced IP density around its specific claimed approach to semiconductor device manufacture. R&D teams can use this signal to identify adjacent process or structural innovations that may be patentable and commercially valuable — particularly in areas not covered by Micron's or Katana's active portfolio assets.
Innovation white spaceSimilar Federal Circuit semiconductor patent validity appeals
Explore Federal Circuit cases involving semiconductor device and manufacturing method patents where unpatentability or invalidity findings were affirmed on appeal.
What this case signals for the semiconductor patent IP landscape
A Federal Circuit affirmance of unpatentability sends a durable signal to assertion entities and manufacturers active in the semiconductor device space.
Unpatentability affirmance raises the bar for similar semiconductor claims
When the Federal Circuit affirms an unpatentability finding, it sets a public record that can be cited in related proceedings. Semiconductor manufacturers facing assertion of structurally similar device or process patents should monitor this decision as potential prior art support for invalidity arguments in future disputes.
Micron's appellate win signals robust invalidity defence capability
Micron Technology's successful defence through the Federal Circuit level — represented by Perkins Coie LLP and Holland & Knight LLP — suggests a well-resourced invalidity litigation posture. Competitors facing similar patent assertions in semiconductor manufacturing should assess whether analogous cancellation proceedings are viable.
Katana v Micron — key questions answered
The United States Court of Appeals for the Federal Circuit affirmed the unpatentability of US6352879B1 in Case No. 24-2103. The court's order states: 'THIS CAUSE having been considered, it is ORDERED AND ADJUDGED: AFFIRMED.' The recorded basis of termination is 'Unpatentable.' The case closed on 21 April 2026, approximately 643 days after filing.
An affirmance of unpatentability by the Federal Circuit means the lower tribunal's determination that US6352879B1 is unpatentable has been upheld on appeal. The patent cannot be enforced as valid. This is a final appellate ruling at the Federal Circuit level; further review would require a petition to the United States Supreme Court. The specific grounds of unpatentability are not detailed in the publicly available order.
US6352879B1, filed as application US09/604081, covers a semiconductor device and method of manufacturing the same. The patent falls within the semiconductor fabrication and device engineering domain. The specific claims and technical details of the patent's scope beyond this description are not reproduced in the available case record.
Katana Silicon Technologies was represented by Carter Arnett PLLC, Cozen O'Connor PC, and Gardella Alciati PA, with counsel including Alexis Leia Ritzer, Howard Lithaw Lim, Michael Clayton Pomeroy, and Scott W. Breedlove. Micron Technology was represented by Holland & Knight LLP and Perkins Coie LLP, with counsel including Amanda Tessar, Amy Elizabeth Simpson, and Andrew Dufresne.
The affirmance directly invalidates US6352879B1. It does not automatically affect other patents in the same family or related applications, which retain their independent legal status. However, the unpatentability finding and its underlying rationale — if publicly available from the lower tribunal — may be cited as supporting precedent in challenges to related patents with overlapping claim scope or shared prosecution history. Practitioners should conduct a full family analysis to assess residual risk.
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