Microreactor Patent Landscape 2026
Microreactor Patent Landscape in 2026
The microreactor patent field is highly concentrated, with Westinghouse Electric Corporation holding a commanding lead and the top five filers together accounting for 56% of the hundred largest filers’ combined records. The field is still expanding on a multi-year basis, though annual volume has eased from its 2021 peak, and the United States anchors the dominant filing jurisdiction.
Westinghouse leads a concentrated field with a widening gap over challengers
Westinghouse Electric Corporation holds the top position by a substantial margin, accumulating 45 patent records — nearly four times the count of the second-ranked filer, Siemens Medical Solutions USA with 12 patent records. The top five filers collectively represent 56% of the hundred largest filers’ combined total, signalling a field where a small group of incumbents controls the dominant share of disclosed innovation.
A clear tier gap separates the leader from the rest of the ranking. Westinghouse’s count is more than three times that of the next nearest rival, and the cluster of filers at 8–12 patent records — Siemens Medical Solutions USA, Rolls Royce Submarines, Radiant Industries, and BWXT Nuclear Energy — forms a second tier that trails significantly. Below them, a long tail of single-digit filers includes both established nuclear vendors and national laboratory operators.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | Westinghouse Electric Corporation | 45 | |
| 2 | Siemens Medical Solutions USA Inc | 12 | |
| 3 | Rolls Royce Submarines Ltd | 10 | |
| 4 | Radiant Industries Inc | 10 | |
| 5 | BWXT Nuclear Energy Inc | 8 | |
| 6 | BWXT Advanced Technologies LLC | 7 | |
| 7 | SHANGHAI NUCLEAR ENGINEERING RESEARCH & DESIGN INS… | 7 | |
| 8 | NuScale Power LLC | 6 | |
| 9 | China Nuclear Power Engineering Co Ltd | 5 | |
| 10 | Crowley Government Services Inc | 4 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Prodigy Clean Energy Ltd | 4 | |
| 12 | Battelle Energy Alliance LLC | 4 | |
| 13 | Global Energy Research Associates LLC | 2 | |
| 14 | Triad National Security LLC | 2 | |
| 15 | Van Uitert Zoet Vera | 2 | |
| 16 | Ball Carroll Edward | 2 | |
| 17 | Rolls-Royce PLC | 2 | |
| 18 | Walsh Engineering Services PC | 2 | |
| 19 | Kolb Hartmuth C | 2 | |
| 20 | Elizarov Arkadij M | 2 |
Westinghouse’s position, reinforced by a recent momentum of +155% growth in recent filings, suggests active portfolio expansion rather than maintenance. The entry of Rolls Royce Submarines, Radiant Industries, BWXT Advanced Technologies, NuScale Power, China Nuclear Power Engineering, and Battelle Energy Alliance as new entrants indicates that the competitive base is broadening, even if the leader’s share remains dominant.
Patent records filed in the most recent 18–24 months are subject to publication lag and are likely under-counted; apparent softness in 2025–2026 data should not be interpreted as a real slowdown. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Activity surged from 2020 and technology composition is overwhelmingly nuclear-reactor focused
The filing trend reveals a step-change in activity beginning in 2020, while the technology composition shows that nuclear reactor classification codes dominate, with a set of adjacent branches accounting for a smaller but meaningful share of records.
Annual filing trend
Filings were negligible before 2020, then spiked sharply to a 2021 peak of 31 records before easing. The 2022 trough of 7 records was followed by a recovery to 17 in 2023 and 27 in 2024. The 2025 figure of 20 and the 2026 figure of 3 are subject to publication lag and do not represent the final counts for those years. The overall multi-year growth of 11% confirms the field is still expanding on a portfolio basis.
↗ Hover for values · click a bar to ask EurekaTechnology composition
G21C (Nuclear reactors) accounts for 126 patent records, making it the overwhelming primary branch. G21D (Nuclear power plants) adds 30 records. Beyond these two dominant nuclear-system classes, smaller clusters appear in B01J (Chemical and physical processes), G21F (Radiation protection and shielding), and B63B (Ships and marine vessels), reflecting microreactor applications in chemistry synthesis, shielding design, and marine propulsion respectively.
↗ Hover for values · click a bar to ask EurekaHighly cited patent families surfaced by the query
Citation-heavy patent families returned by the query. Use this section as citation context, not as a curated list of the most topic-specific patents.
Compact mobile reactor system using high density n…
Described herein are mobile nuclear micro-reactors, systems for same, as well as methods of making mobile nuclear micro-reactors in the hundreds of kilowatt range, scalable to higher powers, capable of operating, at least, ten years without refueling while designed to eliminate fuel resupply tails that have proven so costly in conflicts over the past two… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Offshore and marine vessel-based nuclear reactor c… | 77 |
| 2 | Modular System for Radiosynthesis with Multi-Run C… | 69 |
| 3 | Apparatus and Method Using Rotary Flow Distributio… | 52 |
| 4 | Modular system for radiosynthesis with multi-run c… | 29 |
| 5 | Apparatus and method using rotary flow distributio… | 19 |
| 6 | Modular system for radiosynthesis with multi-run c… | 16 |
| 7 | Nuclear reactor | 16 |
| 8 | Microfluidic radiosynthesis system for positron em… | 14 |
Ranked by total forward citations. Citation counts favour older and broadly cited patent families, and broad or adjacent patents may appear when they match the search scope. Treat this section as citation context, not as a curated list of the most topic-specific patents. Some patent titles may be shown in their original, non-English language where an accurate translation could not be guaranteed.
What the landscape structure means for R&D investment decisions
The combination of a maturing lifecycle, high concentration, a nascent collaboration network, and US-dominant geography shapes both the risks and entry points for new participants.
Field is maturing: annual volume has plateaued near its 2021 peak
The lifecycle stage is Maturity, with annual filings having plateaued near their 2021 peak of 31 records. The multi-year growth figure of 11% confirms the corpus is still growing in aggregate, but the era of rapid annual acceleration has passed. New entrants face an established prior-art base concentrated in nuclear reactor design and must differentiate by application niche or technology sub-class to avoid direct overlap with existing portfolios.
Lifecycle: MaturityTop-heavy ranking creates barriers but also exposes niche gaps
With the top five filers representing 56% of the hundred largest filers’ combined records and Westinghouse alone holding 45 patent records, the field is highly concentrated at the top. This creates freedom-to-operate risk for engineers working near core nuclear reactor design (G21C). However, the long tail of single-digit filers across diverse IPC branches signals that many adjacent application areas remain sparsely protected and accessible to focused entrants.
High concentrationCollaboration is limited: one documented co-filing partnership identified
The evidence shows a single active co-applicant pair: BWXT Advanced Technologies and Crowley Government Services, who have co-filed 4 patent records together. This is the only documented collaboration in the dataset, suggesting the broader ecosystem relies primarily on independent filing strategies rather than joint IP development. An R&D team seeking partnership leverage would find very few existing co-development models to reference within this corpus.
Thin collaboration networkUS-dominant filings with meaningful PCT and EPO coverage
The United States leads with 48 patent records, followed by WIPO PCT applications at 28 and the European Patent Office at 18. Canada and South Africa each hold 10 records, reflecting specific regulatory or deployment interest in those markets. China holds only 4 records despite having two active Chinese applicants, suggesting that Chinese entities may be prioritising domestic filing channels or that their international protection strategy is still developing. Japan and Australia each hold 1 record, indicating limited coverage in those markets.
US-centric, selective internationalGo beyond the landscape: Eureka’s TRIZ Solution agent breaks down an R&D problem and returns patented concept solutions, each with a technical approach and cited patent & literature evidence.
| Applicant | Collaborator | Co-filings |
|---|---|---|
| BWXT Advanced Technologies LLC | Crowley Government Services Inc | 4 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Westinghouse dominates reactor design; challengers differentiate by application focus
The top two filers illustrate the breadth of the microreactor IP space: the field leader concentrates on core nuclear reactor engineering, while the second-ranked filer spans both nuclear and radiochemical synthesis applications.
Westinghouse Electric Corporation
Westinghouse holds 45 patent records, the largest count in the corpus, focused tightly on nuclear reactor engineering across G21C 15 (reactor cooling systems), G21C 1 (reactor types), and G21C 5 (reactor fuel elements). Recent momentum is strongly positive at +155% versus the prior period, indicating active portfolio expansion rather than a defensive maintenance posture. This concentration in core reactor classes makes Westinghouse the principal prior-art risk for any entrant targeting mainstream microreactor design.
patent records: 45Siemens Medical Solutions USA
Siemens Medical Solutions USA holds 12 patent records, placing it second in the ranking. Its technology emphasis is notable for spanning both G21C 1 (nuclear reactor types) and B01J 19 / B01J 8 (chemical and physical processes including flow chemistry), reflecting its involvement in microreactor applications for radiopharmaceutical synthesis — a distinct application domain from the reactor-engineering focus of most other top filers. No momentum data is available in the evidence for Siemens, so trajectory cannot be characterised.
patent records: 12| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Westinghouse Electric Corporation | 28 | ▲ +155% |
| Rolls Royce Submarines Ltd | 5 | ▲ new entrant |
| Radiant Industries Inc | 2 | ▲ new entrant |
| BWXT Advanced Technologies LLC | 4 | ▲ new entrant |
| NuScale Power LLC | 1 | ▲ new entrant |
| China Nuclear Power Engineering Co Ltd | 2 | ▲ new entrant |
| Battelle Energy Alliance LLC | 3 | ▲ new entrant |
Under-served adjacent branches worth monitoring
Several IPC branches appear in the microreactor corpus with low record counts relative to the dominant nuclear classes, representing areas where the existing prior-art base is sparse. These observations indicate relative sparsity; they should be evaluated against technical feasibility and business rationale before being treated as entry opportunities.
G21F · Radiation Protection and Shielding
With 9 patent records and a 4% share among the top-branch classes, radiation protection and shielding is an adjacent branch that is directly coupled to microreactor deployment — compact reactors require purpose-designed shielding solutions distinct from large-plant approaches. The sparse prior-art base suggests that detailed shielding architectures optimised for microreactor geometries, portable deployments, or marine applications have not yet been heavily protected, creating a plausible entry path for materials scientists or structural engineers specialising in compact nuclear systems.
Search this in Eureka →B63B · Ships and Marine Vessels
Eight patent records — a 3% share — cover microreactor applications in the context of ships and marine vessels, a count that is disproportionately low given that Rolls Royce Submarines and BWXT Advanced Technologies both show marine-related IPC codes in their technology emphasis. The intersection of nuclear propulsion, maritime regulatory frameworks, and compact reactor engineering remains a relatively open space in this corpus. Entrants with naval architecture or marine systems expertise could find sparse prior art in specific vessel integration sub-classes.
Search this in Eureka →How leading applicants differ by technology route
Strength of each leader across the main technology routes.
| Player | G21C 1 · Nuclear reactors | G21C 15 · Nuclear reactors | G21C 5 · Nuclear reactors | G21C 7 · Nuclear reactors | G21C 3 · Nuclear reactors |
|---|---|---|---|---|---|
| Westinghouse Electric Corporation | Strong · 17 | Strong · 19 | Strong · 15 | Strong · 10 | Moderate · 8 |
| BWXT Nuclear Energy Inc | Strong · 7 | Absent | Strong · 8 | Absent | Strong · 7 |
| Siemens Medical Solutions USA Inc | Strong · 12 | Absent | Absent | Absent | Absent |
| Radiant Industries Inc | Strong · 5 | Absent | Strong · 5 | Absent | Emerging · 1 |
| Rolls Royce Submarines Ltd | Absent | Moderate · 3 | Absent | Strong · 7 | Absent |
| Shanghai Nuclear Engineering Research & Design Institute Co Ltd | Absent | Strong · 6 | Absent | Absent | Emerging · 1 |
| Battelle Energy Alliance LLC | Absent | Absent | Moderate · 1 | Strong · 4 | Absent |
Frequently asked questions
The corpus covers 121 patent families in scope. This is the total family count used as the basis for the landscape analysis.
Westinghouse Electric Corporation leads with 45 patent records, nearly four times the count of the second-ranked filer. Its filings concentrate heavily in core nuclear reactor engineering sub-classes within G21C.
The United States leads with 48 patent records, followed by WIPO PCT applications at 28 and the European Patent Office at 18. Canada and South Africa each hold 10 records. China holds 4 records despite having two active Chinese applicants in the ranking.
The field is assessed as Maturity. Annual filings have plateaued near their 2021 peak of 31 records. The multi-year corpus still shows an 11% growth figure, meaning the aggregate portfolio is expanding, but the sharp annual acceleration phase that began in 2020 has eased.
One co-applicant collaboration is documented in the evidence: BWXT Advanced Technologies and Crowley Government Services have jointly filed 4 patent records. No other co-filing partnerships are identified in the corpus.
Several adjacent branches have low record counts relative to the dominant G21C class: G21F (Radiation protection and shielding) has 9 records, B63B (Ships and marine vessels) has 8, F02C (Gas-turbine plants) has 5, and B01J (Chemical and physical processes) has 12. These observations indicate relative sparsity and may warrant closer investigation depending on an organisation’s specific technical and commercial focus.
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Disclaimer. This page is generated from PatSnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing on this page constitutes an exhaustive prior-art, novelty, freedom-to-operate, or validity search, nor does it constitute legal, financial, investment, or professional advice, and it should not be relied upon as such. Any patent, commercial, or strategic decision should be verified independently and reviewed with qualified patent, legal, and domain professionals. PatSnap makes no warranties, express or implied, as to the accuracy, completeness, or fitness for any particular purpose of the information presented.