Hydrogen & Fuel Cell Patents: Top Companies & Filing Trends 2026
- 10.3% concentration at the top. The five leading assignees hold 21,507 of the 209,522 records in scope — a real lead, but nowhere near control of the field.
- Filing has cooled from its 2022 peak. Annual filings ran from 619 in 2021 to 341 in 2024, a 45% pullback over that span, before the most recent, still-incomplete years.
- H01M dominates the IPC mix by a wide margin. Batteries, cells and fuel cells (H01M) touch 9.0% of all records — roughly eighteen times the share of the next largest subclass, C01B.
Filing growth compares 2021 (619 records) with 2024 (341) — a three-year span. 2024 is the most recent year we treat as complete: publication lags filing by roughly 18 months, so 2025 onwards are still filling in and any growth rate that ends there would understate the field. Top-5 share is the combined record count of the five largest assignees divided by all 209,522 records in scope (CR5), not by the ranked leaders only.
What this landscape covers
This dataset spans 209,522 published records filed against hydrogen energy, fuel cells and green ammonia, cross-referenced against eight technology tags spanning water electrolysis, low-carbon hydrogen production, hydrogen transport, refuelling infrastructure, industrial use and metallurgy. Coverage runs from 2015 through the third quarter of 2026, though the most recent 18 months of filings are understated because publication lags filing by roughly that long.
The picture that emerges is a technology occupied mainly at the vehicle and stack level rather than at the electrolysis or ammonia-synthesis stage. Battery-and-fuel-cell classifications carry the bulk of the claim density; the upstream production chemistry (C01B, C25B) and catalysis (B01J) sit an order of magnitude lower, which is where less-crowded claim space tends to survive.
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Filing trends and technology composition
Two views of the same 209,522-record corpus: the pace of filing year over year, and how records distribute across the IPC subclasses that define the field's technical core.
A decade of filing, with a 2022 peak
Annual filings rose from 549 in 2017 to a peak of 722 in 2022, then eased to 341 by 2024 — a 45% decline across the 2021-2024 window. Years after 2024 are not yet complete in the record and should not be read as a continued fall.
H01M carries the field; upstream chemistry lags
H01M (batteries, cells & fuel cells) touches 9.0% of all 209,522 records, dwarfing every other subclass tracked here. B60L (EV propulsion) sits at 0.5%, and the production-chemistry classes — C01B, C25B, B01J — each sit at 0.3% or below, marking the electrolysis and catalysis side as comparatively thin ground.
Shares are the percentage of the 209,522 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Hydrogen, Fuel Cells & Green Ammonia Patent Landscape with Eureka
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Try EurekaThe most-cited foundational filings
Systems, methods, and storage medium for controlling hydrogen refueling actions of fuel cell vehicles
Discloses a system, method and storage medium for controlling hydrogen refuelling actions of a fuel cell vehicle: obtaining structural design parameters of the vehicle's hydrogen system and a driving data set, determining first and second hydrogen-refuelling feature sets, detecting a high-hydrogen-consumption state, and issuing a consumption-reduction command that the vehicle control unit executes against the fuel cell system.Filed by China Automotive Technology & Research Center, published 2026-07-16 — illustrates the shift toward refuelling-behaviour software claims layered on top of established hardware.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US5599638A | Aqueous liquid feed organic fuel cell using solid polymer electrolyte membrane | 557 |
| 2 | US5170124A | Method and apparatus for monitoring fuel cell performance | 503 |
| 3 | US5759712A | Surface replica fuel cell for micro fuel cell electrical power pack | 479 |
| 4 | US4522894A | Fuel cell electric power production | 471 |
| 5 | US6013385A | Fuel cell gas management system | 467 |
| 6 | US5273837A | Solid electrolyte fuel cells | 413 |
| 7 | US5372617A | Hydrogen generation by hydrolysis of hydrides for undersea vehicle fuel cell energy systems | 408 |
| 8 | US5767584A | Method for generating electrical power from fuel cell powered cars parked in a conventional parking lot | 389 |
| 9 | US6326097B1 | Micro-fuel cell power devices | 379 |
| 10 | US20070259217A1 | Materials and configurations for scalable microbial fuel cells | 373 |
Citation counts reflect influence within this searched corpus and skew toward older filings — treat them as a signal of foundational status, not of current commercial relevance.
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Three read-throughs from the filing trend, the IPC mix and the citation table, translated into what they mean for where to file and what to watch.
Growth has cooled from a 2022 high, not collapsed
Filings ran from 619 in 2021 to 341 in 2024. That is a real pullback, but it follows a 2022 peak of 722 and sits within a decade where 2017 opened at 549 — the field is normalising off a filing surge, not exiting.
The stack is crowded; the chemistry upstream is not
H01M (batteries, cells & fuel cells) claims 9.0% of all 209,522 records. Electrolytic production (C25B) and inorganic compound chemistry (C01B) each sit at 0.3%, suggesting new stack-level claims face denser prior art than new electrolysis or ammonia-synthesis claims.
A real lead at the top, but a long tail beneath it
The five leading assignees combine for 21,507 records, 10.3% of all records in scope; the top ten add up to 14.6%. That leaves the large majority of filing activity spread across the remaining ranked entrants and unranked filers.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to hydrogen, fuel cells & green ammonia patent landscape, with the prior art for and against each one.
| Assignee | Co-assignee | Shared families |
|---|---|---|
| Hyundai Motor Company | Kia Corporation | 237 |
| Toyota Motor Corporation | Cataler Corporation | 26 |
| UTC Power Corporation | REISER CARL A | 25 |
| Ballard Power Systems Inc. | WILKINSON DAVID P | 23 |
| Honda Motor Co., Ltd. | OGAWA TETABUYA | 22 |
| Ballard Power Systems Inc. | MCLEAN GERARD FRANCIS | 21 |
| UTC Power Corporation | BREAULT RICHARD D | 20 |
| Ballard Power Systems Inc. | Johnson Matthey Plc (UK) | 18 |
Only ten co-assignee pairs appear in this corpus, and one pairing accounts for the bulk of that co-filing activity — most assignees here file solo rather than jointly.
The assignee landscape
The ranking covers 100 companies, counted in records — not a top-50 or top-100 cut of a larger list, but the full set the data endpoint returns. Filing is led by automakers and fuel-cell specialists, with momentum data showing even the leaders pulling back year over year.
One filer sits well ahead of the field
The top-ranked assignee holds 6,426 records, more than double the fifth-place holder's 3,083 and nearly four times tenth place's 1,633 — a steep drop-off rather than a gradual one.
Even the top filers are down sharply in the latest year
Recent-year momentum shows several of the largest historical filers down 91-95% year over year, each reduced to a single filing in the latest period. This tracks with publication lag rather than necessarily a real halt in R&D.
Joint filing is the exception, not the rule
Only ten co-assignee pairings exist in this corpus, and the strongest pairing is far larger than the rest — most organisations here prosecute independently.
| Assignee | Recent year | YoY |
|---|---|---|
| Toyota Motor Corporation | 1 | -93% |
| Honda Motor Co., Ltd. | 1 | -95% |
| Bloom Energy Corporation | 1 | -94% |
| Hyundai Motor Company | 1 | -91% |
| General Electric Company | 1 | -50% |
| Nissan Motor Co., Ltd. | 0 | — |
| GM Global Technology Operations LLC | 0 | -100% |
| Ballard Power Systems Inc. | 0 | — |
Where to take this analysis
The figures here establish the shape of the field. Turning that into a filing or freedom-to-operate decision means going deeper on the specific claims and assignees that matter to your work.
Run a freedom-to-operate check on your own claim set
Use the most-cited records and the representative recent filing as a starting point to see what specific claim language is already occupied before drafting new claims in fuel cell stack or refuelling-control areas.
Check claims in EurekaTrack the leading assignees' recent momentum
The pullback among top filers in the latest year may reflect publication lag rather than a real slowdown — set up monitoring to catch the correction once later filings publish.
Set up monitoring in EurekaExplore the under-claimed chemistry branches
Electrolysis, catalysis and separation classes carry far lower filing density than the fuel-cell stack — worth a dedicated search before assuming the whole hydrogen space is crowded.
Explore white space in EurekaCommon questions about this landscape
The ranking behind this dataset covers 100 companies, led by a single assignee with 6,426 records — more than double the fifth-place holder's 3,083. The leaders are concentrated among automakers and fuel-cell specialists, but the top five together hold only 10.3% of all 209,522 records in scope, so no single company controls the field. A long tail of ranked and unranked entrants files the remaining majority.
Filing peaked in 2022 at 722 records and declined to 341 by 2024, a 45% drop across that three-year span, after rising from 549 in 2017. That reads as a cooling from a filing surge rather than an exit from the field. Years from 2025 onward are not yet complete in the data because publication typically lags filing by around 18 months, so recent-year figures should not be read as the final word on current activity.
H01M — batteries, cells and fuel cells — dominates the technology composition, touching 9.0% of all 209,522 records in scope. Every other subclass tracked sits far lower: EV propulsion (B60L) at 0.5%, and the upstream production chemistry classes (C01B, C25B) each around 0.3%. That gap suggests the fuel-cell stack itself is the most heavily claimed part of the value chain, with electrolysis and synthesis chemistry comparatively open.
Based on IPC composition, the sub-areas with the lowest filing density relative to the fuel-cell core include electrolytic hydrogen production catalysis, aircraft fuel-cell power systems, hydrogen purification via separation membranes, and hydrogen-based metallurgy processes — each sitting at 0.3% of records or below versus H01M's 9.0%. Low density does not guarantee an easy filing, but it does mean less prior art to design around in a first claim.
That filing, from China Automotive Technology & Research Center and published 2026-07-16, claims a system and method for controlling hydrogen refuelling actions in a fuel cell vehicle — specifically detecting high-hydrogen-consumption states from driving and structural data and issuing a consumption-reduction command to the vehicle control unit. It sits at the software-and-control layer rather than the hardware layer, so it is most relevant to anyone building refuelling-behaviour logic on top of an existing fuel-cell stack, not to core stack or membrane work. Whether it blocks a given design depends on the exact claim scope, which should be reviewed directly rather than inferred from the abstract alone.
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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.
Machine translation. Assignee and organisation names originally recorded in Chinese, Japanese or Korean have been rendered into English by an AI translation step so that the tables stay readable. These renderings are best-effort and may not match a company’s registered English name; the original name is what the underlying patent record carries, and it is what any Eureka query launched from this page uses.