Electrodialysis Desalination Patents: Leaders & Trends 2026
- Filing has cooled since its 2023 peak of 42 families. growth between the 2022 midpoint (37) and the peak was flat, and the partial 2026 count of 1 confirms the slowdown rather than a data gap.
- Claims cluster overwhelmingly in water treatment and separation. C02F and B01D account for 481 and 411 of the 589 families respectively, dwarfing adjacent IPC classes like C25B and C01B.
- The US is the dominant receiving office by a wide margin. 166 filings land there against 85 in China and 72 at the EPO, signalling where enforcement risk concentrates first.
Filing growth compares 2021 (33 records) with 2024 (26) — 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 589 records in scope (CR5), not by the ranked leaders only.
What the electrodialysis desalination patent record shows
Electrodialysis and electrodialysis reversal (EDR) desalination has drawn 589 patent families published between 2017 and the 2026 data cut-off, concentrated tightly around water and wastewater treatment (C02F) and membrane separation (B01D) rather than spread across adjacent electrochemical fields. Filing rose steadily through the late 2010s, peaked at 42 families in 2023, and has since flattened — the 2022 midpoint of 37 sits close enough to the peak that the intervening years read as a plateau, not a breakout.
Because publication lags filing by roughly eighteen months, the 2025 and 2026 counts in any such trend understate real filing activity; treat the visible slowdown as a floor, not a confirmed peak-and-decline. The most-cited records in the corpus date from the 1980s and 1990s, which is normal for citation counts inside a searched corpus — older foundational patents accumulate citations simply by having been available longer, not because current filers are building primarily on them.
Filing trend and technology composition
Annual filings and IPC distribution across the 589 families in this dataset, spanning receiving offices in the US, China, Europe, WIPO, Canada and India.
A decade of filing activity, now plateaued
From 9 families in 2017 to a peak of 42 in 2023, then flattening — the 2022 figure of 37 shows the climb had already largely finished a year before the peak.
Concentrated in water treatment and separation
C02F (481) and B01D (411) dominate; smaller counts in B01J, C08J, H01M, C12P, C01B and C25B mark adjacent fields — catalysis, polymer chemistry, electrochemical production — that touch the technology without owning it.
Shares are the percentage of the 589 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Electrodialysis Desalination with Eureka
This page is one run against one query. Ask Eureka your own question about electrodialysis desalination and every answer comes back with the patent numbers behind it.
Try EurekaFoundational and representative filings
Ion conductive spacer for electrodialysis reversal stacks (US20190358589A1)
An ion conductive spacer for use in an electrodialysis reversal stack is disclosed, which includes a plastic netting and a polymeric coating coated on the plastic netting and containing charged groups. The morphology of the polymeric coating has interconnected ionic clusters which allow continuous and macroscopic ion transportation throughout a surface of the plastic netting. An electrodialysis reversal stack using the above ion conductive spacer and a process for preparing the above ion conductive spacer are also disclosed.Filed by BL Technologies, Inc. — illustrates how spacer and coating chemistry, rather than the electrodialysis principle itself, is where recent claim activity concentrates.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US5503729A | Electrodialysis including filled cell electrodialysis (electrodeionization) | 125 |
| 2 | US5240579A | Electrodialysis reversal process and apparatus with bipolar membranes | 117 |
| 3 | US3341441A | Method for preventing scale buildup during electrodialysis operation | 111 |
| 4 | US4676908A | Waste water treatment | 105 |
| 5 | US4871431A | Apparatus for the removal of dissolved solids from liquids using bipolar membranes | 104 |
| 6 | WO2002014224A1 | Device and method for electrodialysis | 82 |
| 7 | US20070215474A1 | Electrodialysis System and Process | 77 |
| 8 | US5679229A | Electrodialysis including filled cell electrodialysis (electrodeionization) | 73 |
| 9 | US7585652B2 | Recovery of inorganic salt during processing of lignocellulosic feedstocks | 71 |
| 10 | US5814197A | Electrodialysis including filled cell electrodialysis (electrodeionization) | 69 |
Citation counts favour older filings simply because they have had longer to accumulate references — read this table as a map of influence, not of current commercial relevance.
Each row carries its publication number; clicking a row searches Eureka by that number.
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Four patterns stand out once the trend, geography and technology composition are read together.
The growth phase is over, at least on paper
The climb from 9 families in 2017 to 42 in 2023 was steady rather than explosive, and the 2022 figure of 37 shows most of that growth had already happened before the peak year. Publication lag means the last one to two years understate real activity, but the plateau at the midpoint suggests this is a maturing field, not one still accelerating.
Claim space sits almost entirely in two classes
Water/wastewater treatment and membrane separation between them touch the overwhelming majority of families. Smaller counts in H01M (34), C01B (24) and C25B (24) mark electrochemical and materials adjacencies that are present but far from saturated.
The US is the first enforcement front
With 166 filings against 85 in China and 72 at the EPO, freedom-to-operate diligence for this technology should start with US prosecution history before extending to WIPO's 66 PCT filings or the smaller Canadian and Indian counts.
Collaboration is limited and centres on one hub
Only 10 co-assignee pairs appear across the corpus, and the strongest links all route through the same organisation, pairing with individual inventors and one corporate partner at counts of 3 to 5. Most families in this space are filed by a single assignee acting alone.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to electrodialysis desalination, with the prior art for and against each one.
Who holds the claim space, and where momentum has gone quiet
Recent-year momentum across the tracked assignees is uniformly flat: every named organisation in this dataset shows zero filings in the latest year, with two recording a full year-on-year drop to zero. That pattern, combined with the plateaued trend, points to a field where incumbents are holding position rather than expanding it.
A long-running filer now inactive on paper
The organisation with the deepest co-assignee network in this corpus — appearing in all three of the strongest joint-filing pairs — shows no filings in the most recent tracked year, consistent with the broader plateau rather than an isolated event.
Research-institution filing has dropped to zero
An academic assignee in the dataset shows a full year-on-year decline to zero filings, a pattern also seen at a major water-technology specialist. Academic filers in this space tend to file selectively around specific membrane or electrode innovations rather than maintaining a steady pipeline.
A dedicated water-treatment technology assignee has also gone quiet
Alongside the academic filer, a water-treatment technology specialist shows the same year-on-year drop to zero, reinforcing that the slowdown is not confined to one type of organisation — corporate and institutional filers show the same pattern.
| Assignee | Recent year | YoY |
|---|---|---|
| General Electric Company | 0 | — |
| AGC Inc. | 0 | — |
| Massachusetts Institute of Technology (MIT) | 0 | -100% |
| Enviro Water Minerals Company | 0 | — |
| Saltworks Technologies Inc. | 0 | — |
| Evoqua Water Technologies LLC | 0 | -100% |
| MAGNA IMPERIO SYST | 0 | — |
| Yeda Research and Development Co. Ltd. | 0 | — |
Where to take this analysis
The filing trend and IPC composition point to specific next steps depending on whether the goal is freedom-to-operate, licensing or new R&D.
Map the spacer and coating sub-claims
Recent representative filings concentrate on spacer material and coating chemistry rather than the core electrodialysis process — a narrower, more current layer worth mapping claim-by-claim.
Explore in Eureka →Track the quiet incumbents for renewed activity
Several long-standing assignees show zero filings in the latest year; a fresh filing from any of them would be an early signal of the next growth phase in this plateaued field.
Set up monitoring in Eureka →Check the under-claimed adjacencies
H01M, C01B and C25B overlaps are present but thin relative to the C02F/B01D core, suggesting room for narrowly drawn claims in electrochemical co-production and hybrid separation.
Run a white space search in Eureka →Common questions about electrodialysis desalination patents
This dataset tracks 589 patent families published between 2017 and the 2026 data cut-off, drawn from a search combining electrodialysis and electrodialysis-reversal terminology with the relevant IPC codes (B01D61/44, C02F1/469, C02F1/46). Filing rose from 9 families in 2017 to a peak of 42 in 2023 before flattening. Because publication lags filing by roughly eighteen months, the true count for the most recent one to two years is understated in any such figure.
The corpus shows filing concentrated among a small set of corporate and institutional assignees, with one organisation standing out for its co-assignee network — it appears in all of the strongest joint-filing pairs in the dataset. Several major assignees, including a leading water-technology specialist and an academic research institution, show zero filings in the most recent tracked year. That pattern suggests the field currently has incumbents holding position rather than new entrants displacing them.
Not clearly. Filing climbed steadily from 9 families in 2017 to a peak of 42 in 2023, but the 2022 count of 37 was already close to that peak, meaning most of the growth had happened before the peak year rather than during a late surge. The partial 2026 count of 1 and uniformly flat recent-year momentum across tracked assignees both point to a plateau rather than continued expansion, though publication lag makes the very latest years look weaker than they likely are.
The core claim space sits in water/wastewater treatment (C02F, 481 records) and membrane separation (B01D, 411 records), which together dominate the corpus. Smaller but notable overlaps appear in catalysis and physical processes (B01J), polymer processing (C08J), batteries and fuel cells (H01M), fermentation (C12P), inorganic chemistry (C01B) and electrolytic production (C25B) — each in the 24-to-53 record range, marking adjacent fields that touch the technology without dominating it.
The thinner IPC classes in this dataset — C25B (electrolytic production), C01B (inorganic compounds) and H01M (batteries and fuel cells) — sit at 24 to 34 records each against 481 in the core C02F class, suggesting these overlaps are under-claimed relative to the core process. Specific sub-areas worth checking include bipolar membrane fouling mitigation, ion-exchange spacer coating chemistry, and electrodialysis-fermentation hybrid separation, none of which show the same filing density as the core desalination claims.
US20190358589A1, assigned to BL Technologies, Inc. and published in 2019, covers an ion conductive spacer for electrodialysis reversal stacks — specifically a plastic netting coated with a polymeric coating containing charged groups that forms interconnected ionic clusters for ion transport across the spacer surface. It also claims the electrodialysis reversal stack built using that spacer and the process for preparing it. This is a materials and manufacturing-process claim rather than a claim on the electrodialysis principle itself, so it primarily affects anyone designing spacer or coating chemistry for ED/EDR stacks.
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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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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.