Nuclear Fuel Assembly Patents: Who Leads, Where the Gaps Are 2026
Nuclear fuel assembly design patents: who holds the cladding and grid-spacer claims
66.8% concentration. The top five assignees hold 308 of 461 records in scope — a field where the core claim space is already staked out by a small group of reactor OEMs and national labs. Volume peaked at 26 records in 2017 and has declined since, with 2021 at 15 falling to 3 by 2024 — an 80% drop across that span. 2025 and 2026 figures will rise as publication catches up with filing, so read the tail as incomplete rather than as continued decline.
- 1WESTINGHOUSE ELECTRIC CORP176
- 2GENERAL ELECTRIC CO48
- 3KOREA ATOMIC ENERGY RES INST33
- 4KOREA HYDRO & NUCLEAR POWER CO LTD27
- 5SIEMENS NUCLEAR POWER CORP24
See the full nuclear fuel assembly design analysis in Eureka
- The complete ranking, not just the top five
- Every IPC branch with its share of the corpus
- The most-cited records, and where claim space is still thin
Common questions about nuclear fuel assembly patents
Who holds the most patents in nuclear fuel assembly design?
One assignee leads with 176 of the 461 records in this dataset, well ahead of the rest of the ranked field. The top five assignees combined hold 308 records, or 66.8% of everything in scope, so the field’s core mechanical claims are concentrated among a small group of established reactor OEMs and national nuclear research institutes rather than spread evenly. Beyond the top ten, which together hold 82.0% of records, filing volume drops off steeply into a long tail of single- or few-filing entrants.
Is patent filing in nuclear fuel assembly design growing or shrinking?
Filing peaked at 26 records in 2017 and has declined since, falling from 15 records in 2021 to 3 in 2024 — an 80% drop across that three-year span. Because publication typically lags filing by around 18 months, the 2025 and 2026 figures in any dataset will understate true filing activity and should not be read as confirming a further decline. Taken through 2024, the last year that can be treated as complete, the trend is a genuine multi-year contraction from the 2017 peak.
What technologies dominate nuclear fuel assembly patent claims?
The IPC subclass G21C, covering nuclear reactors generally, appears in 91.3% of the 461 records in scope, meaning nearly every filing is framed as reactor-core hardware. Materials-focused classes are smaller: alloys (C22C) appear in 12.4% of records, coating and surface deposition (C23C) in 5.4%, and ceramics (C04B) in 3.3%. Because a single record can carry multiple IPC classes, these figures do not sum to 100% — they show where technical emphasis sits, not a strict partition of the field.
Disclaimer. This analysis is based on Patsnap Eureka data drawn from a limited snapshot of global patent records and is provided for general information and reference only. Patent data carries inherent limitations — recent filings are under-counted because of publication lag, counts may be on a record or family basis, classification and applicant-name data may contain errors or duplicates, and the underlying search query defines the scope shown — so the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing here is an exhaustive prior-art, novelty, freedom-to-operate or validity search, nor does it constitute legal, financial or professional advice, and it should not be relied upon as such. Verify independently and review with qualified patent and legal professionals before acting on it.
Method: Filing trend and technology composition. Derived from a Patsnap search on Nuclear Fuel Assembly Design covering 2015–2026, data cut-off 2026-07-31. Counts reflect published records only and shift as new filings publish. Every share divides by all records in scope. Data: Patsnap Eureka. See the full landscape report.