PEM Fuel Cell Alkaline Electrolyzer Patent Landscape
PEM Fuel Cell Alkaline Electrolyzer Patent Landscape in 2026
This is a small but highly concentrated niche: a handful of established European industrial firms — led by Siemens AG — account for the majority of activity, with China emerging as the leading filing jurisdiction. The field is expanding on a multi-year basis, though annual volume has eased from its 2017 peak and the most recent years remain understated by publication lag.
Siemens AG leads a tightly held niche dominated by European industrials
Siemens AG holds the leading position in this landscape, followed by Robert Bosch GmbH, W C Heraeus GmbH, and Mercedes-Benz Group AG. The top five filers collectively represent 69% of the hundred largest filers’ combined patent records, signalling unusually high concentration for an energy-transition technology.
The tier gap between the leader and the rest is pronounced: Siemens AG’s count is roughly 22% larger than the nearest rival. Beyond the top five, all remaining ranked applicants hold only one or two patent records each, indicating a long tail of exploratory entrants rather than a second competitive tier.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | Siemens AG | 11 | |
| 2 | Robert Bosch GmbH | 9 | |
| 3 | W C Heraeus GmbH | 6 | |
| 4 | Mercedes-Benz Group AG | 5 | |
| 5 | Hydrogenics Corp | 5 | |
| 6 | Degussa Huls AG | 2 | |
| 7 | UMICORE AG & CO KG | 2 | |
| 8 | Zhejiang Haizhuo New Energy Technology Co Ltd | 1 | |
| 9 | Indian Oil Corporation Ltd | 1 | |
| 10 | Hangzhou Gongshu District Edge Intelligence Innovation Research Institute | 1 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Ruqing (Qingdao) Energy Technology Co Ltd | 1 | |
| 12 | Honeywell International Inc | 1 | |
| 13 | Tsinghua University | 1 | |
| 14 | Saudi Arabian Oil Company | 1 | |
| 15 | MLR Institute of Technology | 1 | |
| 16 | OMG AG & CO KG | 1 | |
| 17 | North China Electric Power University | 1 | |
| 18 | LEIBNIZ INST FUR PLASMAFORSCHUNG & TECH | 1 | |
| 19 | Zoomlion Heavy Industry Science and Technology Co Ltd | 1 |
The incumbents’ positions — rooted in electrochemical cell design, electrode assemblies, and fluid-flow control — reflect deep manufacturing know-how that creates a meaningful barrier for new entrants working at the stack-integration level.
Patent records filed in the most recent 18–24 months are subject to publication lag and are likely undercounted; the apparent quieting of 2025–2026 activity should not be read as a reversal of the broader multi-year growth trend.
Multi-year growth with a technology mix anchored in electrolysis and cell chemistry
The annual filing chart reveals a 2017 spike followed by a quieter mid-period and a renewed uptick from 2022 onward; the technology composition chart shows that electrolytic production (C25B) and fuel-cell/battery chemistry (H01M) together dominate, with a sparse set of adjacent branches.
Annual filing trend
A notable burst of activity occurred in 2017, after which filings fell to low single-digit levels before recovering from 2022. The three-year recent window sits well above the prior three-year window, confirming net growth of 350% on that basis. The 2025–2026 bars should be treated as floor estimates due to publication lag.
↗ Hover for values · click a bar to ask EurekaTechnology composition
C25B (electrolytic production of compounds) and H01M (batteries, cells, and fuel cells) together account for the overwhelming share of IPC classifications, confirming that core stack and electrode chemistry is where technical effort is concentrated. All other branches — including B32B layered products, B05D coating processes, and B01D separation — each represent a small fraction, pointing to under-developed peripheral work.
↗ 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.
VERBESSERTE MEMBRAN-ELEKTRODEN-EINHEIT FÜR EINE PE…
Die Erfindung betrifft eine Membran-Elektroden-Einheit für eine PEM-Brennstoffzelle, bei der die aktive Elektrodenkatalysatorschicht als trockenes Pulver direkt auf die Membran aufgepresst ist. Ausserdem betrifft die Erfindung ein kostengünstiges und massenfertigungstaugliches Herstellungsverfahren für diese Membran-Elektroden-Einheit (ME), bei dem das… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Improved diaphragm electrode unit for a PEM fuel c… | 79 |
| 2 | Method for applying electrode layers on a tape-lik… | 55 |
| 3 | Control of a fluid flow in an electrochemical cell | 28 |
| 4 | Method and device for generating hydrogen and oxygen | 13 |
| 5 | Method for manufacturing membrane electrode assemb… | 10 |
| 6 | Component such as a cell frame and/or a pole plate… | 9 |
| 7 | Control of a fluid flow in an electrochemical cell | 8 |
| 8 | Control of a fluid flow in an electrochemical cell | 4 |
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 competitive structure means for R&D investment decisions
The combination of high concentration, a named leader with deep technical breadth, and a growing but still modest corpus shapes the strategic calculus for any new entrant or incumbent seeking to expand.
Growth stage with eased annual volume from the 2017 peak
The lifecycle is classified as Growth: the most recent three-year filing window is 350% above the prior equivalent window, confirming that the field is still expanding on a multi-year basis. However, annual volume has eased from its 2017 peak, suggesting that the initial surge of foundational IP has passed and current filings are more selective. The most recent years are further understated by publication lag.
Growth · post-peak cadenceTop five hold 69% of leading-filer activity — a high-barrier core
The top five filers account for 69% of the top hundred filers’ combined patent records, and the gap between Siemens AG at the top and the long tail of single-record entrants is wide. This level of concentration means that core stack architecture and electrode-assembly IP is largely locked up by established European industrials. New entrants are more likely to find room in peripheral technical branches than in the dominant C25B and H01M core.
High concentrationSiemens–W C Heraeus partnership is the defining co-filing relationship
The most active co-filing pair is Siemens AG and W C Heraeus GmbH, with 6 joint patent records — the strongest collaboration signal in the corpus. Individual inventor Waidhas Manfred appears as a co-filer alongside both Siemens AG and W C Heraeus GmbH, indicating a sustained joint-development programme rather than one-off collaboration. Several other named inventors (Jeschonnek Bernd, Hornung Regina, Forderer Heinz) each co-filed with both organizations, reinforcing the depth of this bilateral relationship.
Bilateral industrial JDAChina leads filing jurisdictions; Europe and PCT follow closely
China accounts for the largest share of patent records by jurisdiction, followed by the European Patent Office and WIPO (PCT), then the United States and Canada. The presence of Chinese applicants such as Zhejiang Haizhuo New Energy Technology and a Hangzhou research institute among the ranked filers suggests early-stage domestic IP building in China, even as European incumbents drive the bulk of technical output. Japan, Australia, India, and South Korea each have minimal coverage, indicating geographic white space outside the three primary axes.
China · EPO · PCT triangleGo 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 |
|---|---|---|
| Siemens AG | W C Heraeus GmbH | 6 |
| WAIDHAS MANFRED | Siemens AG | 3 |
| WAIDHAS MANFRED | W C Heraeus GmbH | 2 |
| JESCHONNEK BERND | Siemens AG | 2 |
| JESCHONNEK BERND | W C Heraeus GmbH | 2 |
| HORNUNG REGINA | Siemens AG | 2 |
| HORNUNG REGINA | W C Heraeus GmbH | 2 |
| FORDERER HEINZ | Siemens AG | 2 |
| FORDERER HEINZ | W C Heraeus GmbH | 2 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Siemens AG and Robert Bosch GmbH lead on cell design and stack integration
Two German industrial conglomerates define the competitive frontier: Siemens AG through a broad electrolysis and fuel-cell portfolio built over multiple decades, and Robert Bosch GmbH as a fast-rising challenger with overlapping technology focus and a fresh entrant momentum signal.
Siemens AG
Siemens AG leads the corpus with 11 patent records, concentrated in C25B 9 (electrolytic cell design), H01M 8 (fuel-cell stacks), and C25B 1 (electrolytic compound production). Its deep collaboration with W C Heraeus GmbH — spanning 6 co-filed records — amplifies its effective IP coverage. The breadth of its technical focus across both PEM and alkaline cell architectures makes it the reference point for any freedom-to-operate analysis in this space.
patent records: 11Robert Bosch GmbH
Robert Bosch GmbH holds 9 patent records and is the only applicant for which a momentum signal is available, classified as a new entrant on recent filings. Its technical profile mirrors Siemens AG across C25B 9 and H01M 8, but it also extends into B32B 15 (layered products and laminates) — a branch where Siemens AG has little recorded activity — suggesting a materials-integration angle that could differentiate its stack-assembly approach.
patent records: 9| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Robert Bosch GmbH | 2 | ▲ new entrant |
Under-served technical branches adjacent to the dominant core
Beyond the C25B and H01M core, several IPC branches carry very low patent-record counts relative to their technical relevance to electrolyzer performance and manufacturability — these are observations of relative sparsity that warrant further assessment before treating them as investment targets.
B32B · Layered products and laminates
This branch holds only 4 patent records despite its direct relevance to membrane-electrode assembly (MEA) construction, where layer-by-layer material engineering governs performance and durability. Robert Bosch GmbH is the only top-tier applicant with noted activity here. An entrant with expertise in functional thin-film or composite laminate processing could develop differentiated MEA architectures with limited direct overlap against the dominant Siemens–Heraeus filings.
Search this in Eureka →B22F · Powder metallurgy
Only a single patent record appears under B22F (powder metallurgy), despite the field’s direct applicability to catalyst-layer fabrication and porous transport layer sintering — both critical to electrolyzer efficiency. No top-five applicant shows a meaningful presence here. This gap may reflect the field’s historically chemistry-first approach; a materials-science entrant with powder-processing capabilities could address catalyst ink and diffusion-layer manufacturing with relatively unencumbered IP room.
Search this in Eureka →How leaders differ by technology route across C25B, H01M, and adjacent branches
Strength of each leader across the main technology routes.
| Player | H01M 8 · Batteries, cells & fuel cells | C25B 9 · Electrolytic production of compounds | C25B 1 · Electrolytic production of compounds | C25B 15 · Electrolytic production of compounds | H01M 4 · Batteries, cells & fuel cells |
|---|---|---|---|---|---|
| Robert Bosch GmbH | Strong · 9 | Strong · 9 | Moderate · 3 | Moderate · 3 | Absent |
| Siemens AG | Strong · 8 | Strong · 10 | Emerging · 2 | Absent | Absent |
| Mercedes-Benz Group AG | Strong · 5 | Strong · 5 | Absent | Strong · 5 | Absent |
| W C Heraeus GmbH | Strong · 6 | Strong · 6 | Absent | Absent | Absent |
| Hydrogenics Corp | Strong · 5 | Strong · 5 | Absent | Absent | Absent |
| Degussa Huls AG | Strong · 3 | Strong · 3 | Absent | Absent | Strong · 3 |
Frequently asked questions
The corpus contains 21 patent families in scope. This is a small but technically focused niche, and the modest total means that each individual family carries significant weight in any freedom-to-operate or landscape analysis.
Siemens AG leads with 11 patent records, roughly 22% ahead of the nearest rival, Robert Bosch GmbH, which holds 9 patent records. Together with W C Heraeus GmbH, Mercedes-Benz Group AG, and Hydrogenics Corp, these five applicants account for 69% of the top-hundred filers’ combined records.
The field recorded a notable spike in 2017 before falling to low single-digit annual filings through the mid-period. Activity recovered from 2022 onward, and the most recent three-year window is 350% above the prior equivalent window, confirming net multi-year growth. Annual volume has eased from the 2017 peak. The 2025–2026 figures are understated by publication lag.
C25B (electrolytic production of compounds) and H01M (batteries, cells, and fuel cells) together account for the vast majority of IPC classifications. The most sparsely covered adjacent branches are B32B (layered products and laminates) with 4 records, B05D (coating processes) with 3, and B22F (powder metallurgy) with only 1 record — all potentially relevant to MEA fabrication and catalyst-layer engineering.
China leads by jurisdiction with 12 patent records, followed closely by the European Patent Office with 11 and WIPO (PCT) with 9. The United States has 6 records, and Canada and Spain each have 3. Japan, Australia, India, and South Korea each have minimal coverage.
The most active co-filing relationship is between Siemens AG and W C Heraeus GmbH, with 6 jointly filed records. This partnership is reinforced by several named individual inventors — including Waidhas Manfred, Jeschonnek Bernd, Hornung Regina, and Forderer Heinz — who each co-filed with both organizations, pointing to a sustained bilateral joint-development programme rather than opportunistic co-filing.
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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.
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