Water Treatment Patents: Top Companies & Filing Trends 2026
- No single filer dominates. the top 5 assignees combined account for just 4.8% of the 65,047 records in scope, and the top 10 for 7.8% — this is a fragmented field, not a concentrated one.
- Filing has cooled from its peak. activity peaked in 2018 at 1,121 records and has since eased, with the 2021-to-2024 span (the last fully-published years) down 26%, from 831 to 611.
- Core treatment claims dwarf adjacent ones. C02F (water and wastewater treatment) covers 20.7% of all records and B01D (separation processes) another 9.6%, while sterilising/disinfecting (A61L) sits at just 0.7%.
Filing growth compares 2021 (831 records) with 2024 (611) — 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 65,047 records in scope (CR5), not by the ranked leaders only.
A fragmented field built on core treatment and separation claims
The environmental and water treatment patent landscape spans 65,047 published records filed against a search combining water treatment terminology with functional claims around contaminant removal, membrane flux and treatment efficiency. The field is defined less by a handful of dominant players than by a wide base of filers working similar problems from different angles — reverse osmosis, chemical dosing, membrane fouling control, and increasingly, sensing and detection layered on top of conventional treatment modules.
Two IPC subclasses carry most of the technical weight: C02F, which covers water and wastewater treatment methods directly, and B01D, which covers the separation and filtration processes that much of C02F depends on. Everything else — catalysis, analysis, mixing, disinfection — sits well behind, which is where the more specific, less contested claim space tends to live.
Let an AI agent run this analysis on your own technology
Pick a task. Every answer cites the patents behind it.
Filing trend and technology composition
Filing volumes and IPC composition for the 65,047 records in scope, drawn from publications dated 2015 through the 2026-08-31 cut-off.
Filing trend, 2017–2026
Filings rose to a peak of 1,121 in 2018, then eased. Because publication lags filing by roughly 18 months, the 2025 and 2026 figures (62 in 2026) are still incomplete and understate real filing activity; the last year that can be read as a finished trend is 2024, when filings sat at 611 — down 26% from 831 in 2021.
Technology composition by IPC subclass
C02F (water and wastewater treatment) accounts for 20.7% of the 65,047 records and B01D (separation processes) for 9.6%; because a single record can carry several IPC codes, these shares sum to more than 100% and each is read against the full record count, not against each other.
Shares are the percentage of the 65,047 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Environmental & Water Treatment Patent Landscape with Eureka
This page is one run against one query. Ask Eureka your own question about environmental & water treatment patent landscape and every answer comes back with the patent numbers behind it.
Try EurekaRepresentative filing and most-cited prior art
US11892393B2 — Detection system and method for determining contaminant concentration in feed water stream
A system and method for treating water containing at least one contaminant, combining a water treatment module such as a reverse osmosis unit with an electrochemical contaminant detection system positioned in the waste water stream. A contaminant sensor and a water quality sensor module measure contaminant concentration and water quality parameters, and a processor uses an algorithm to determine contaminant concentration in the feed water from the waste-stream measurements.Filed by A. O. Smith Corporation, published 2024-02-06.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US20160045841A1 | New and improved system for processing various chemicals and materials | 860 |
| 2 | US6949196B2 | Methods and systems for improved dosing of a chemical treatment, such as chlorine dioxide, into a fluid strea… | 591 |
| 3 | US5972196A | Electrochemical production of ozone and hydrogen peroxide | 588 |
| 4 | US20080149561A1 | Articles Comprising a Fibrous Support | 398 |
| 5 | US20070102359A1 | Treating produced waters | 389 |
| 6 | US6113797A | High water recovery membrane purification process | 341 |
| 7 | US6416668B1 | Water treatment process for membranes | 324 |
| 8 | US6569329B1 | Personal water filter bottle system | 296 |
| 9 | US20050139530A1 | Water purifier and method of making and using the same | 286 |
| 10 | US5591317A | Electrostatic device for water treatment | 282 |
Citation counts reflect influence within the searched corpus and skew toward older records; they are not a measure of current commercial importance.
Each row carries its publication number; clicking a row searches Eureka by that number.
Put your own technology through the same analysis
Eureka on the web
When you want the answer in the next five minutes.
The agent works the prompt against patents and technical literature, citing every source.
Run your analysis now →MCP server & REST API
When it has to run inside your own pipeline.
Patent search, landscape analysis and assignee resolution as MCP tools. Drop them into any agent framework, or call REST directly.
Browse MCP servers →What the numbers say about this field
Three patterns stand out once the records are broken down by assignee, class and geography.
Leadership is thin, not absolute
The leading assignee holds 864 records and fifth place holds 474, but combined the top 5 still account for only 4.8% of all records in scope, and the top 10 for 7.8%. No single company has locked up the space — the ranked leaders share a large, active field with many mid-sized and single-filing entrants.
Activity has cooled from its 2018 peak
Filings peaked at 1,121 in 2018 and have since declined, falling from 831 in 2021 to 611 in 2024 — a 26% drop across the last three fully-published years. The 2025–2026 figures are too recent to read as a trend given typical publication lag.
Core treatment claims dominate the class mix
C02F (water and wastewater treatment) and B01D (separation processes) together cover the bulk of claim activity, at 20.7% and 9.6% of records respectively. Adjacent classes — catalysis, testing, disinfection — each sit under 3%, suggesting these are narrower, more specific claim territories.
Filing is US-anchored with strong PCT and EPO routes
The United States receives the largest share of filings at 9,075 records, ahead of Europe (EPO) at 3,280 and the WIPO PCT route at 2,827. Canada and Australia each carry over 1,500 records, pointing to meaningful filing strategy outside the largest markets.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to environmental & water treatment patent landscape, with the prior art for and against each one.
Who is filing, and where momentum is shifting
The assignee ranking covers 100 companies counted by patent family, from large industrial water-treatment specialists down to niche chemical dosing and sensing firms.
The largest single filer, still a small slice of the field
The top-ranked assignee holds 864 records — a meaningful lead over fifth place at 474 — but even this leading position represents a small fraction of the 65,047 records in scope, confirming the field's fragmented structure.
Even active filers are pulling back
Recent-year momentum data shows several of the more established assignees filing zero records in the latest tracked year, with the most active of the group down to just 2 filings, a 50% year-on-year drop. This pattern is consistent with the broader 2021–2024 decline rather than an isolated event.
Co-filing is limited and concentrated
Only 10 co-assignee pairs appear in the dataset, and the strongest of these link a single energy-technology assignee with individual named inventors rather than joint corporate filing. Cross-company collaboration is not a defining feature of this landscape.
| Assignee | Recent year | YoY |
|---|---|---|
| Evoqua Water Technologies LLC | 2 | -50% |
| Crystal Lagoons (Curacao) BV | 0 | — |
| Ecolab USA Inc | 0 | -100% |
| Kurita Water Industries Ltd | 0 | -100% |
| Toray Industries Inc | 0 | — |
| Nalco Company | 0 | — |
| GreatPoint Energy, Inc. | 0 | — |
| General Electric Company | 0 | — |
Where to take this analysis
The dataset points to a field with room at the edges even as core treatment classes stay dense.
Map claim density before drafting
C02F and B01D carry the bulk of filing activity, so new claims aimed squarely at core water treatment or separation methods will meet the densest prior art. Checking claim scope against this density early avoids rework later.
Explore the technology in EurekaTrack momentum, not just rank
Several ranked leaders show flat or declining recent-year filing, which changes who is worth watching versus who simply has legacy volume. Momentum data separates active competitors from historical ones.
Run a live assignee search in EurekaWatch the sensing-and-detection layer
Representative filings like US11892393B2 combine treatment modules with contaminant detection, a pairing that sits across multiple IPC classes rather than inside one. This layer is worth a dedicated search rather than assuming it is captured under C02F alone.
Search cross-class filings in EurekaCommon questions about this landscape
The assignee ranking covers 100 companies counted by patent family, and it is a fragmented field rather than one dominated by a single player. The leading assignee holds 864 records, but the top 5 assignees combined account for only 4.8% of the 65,047 records in scope, and the top 10 for 7.8%. This means a competitive scan needs to look well beyond the largest few names, since a large share of filing activity sits with mid-sized and single-filing entrants.
Filing activity peaked in 2018 at 1,121 records and has eased since. Looking at the last three fully-published years, filings fell from 831 in 2021 to 611 in 2024, a 26% decline. Figures for 2025 and 2026 look lower still, but that is expected — publication typically lags filing by around 18 months, so the most recent years are always undercounted at the point of measurement.
Two IPC subclasses carry most of the claim activity: C02F, covering water and wastewater treatment methods, at 20.7% of the 65,047 records in scope, and B01D, covering separation and filtration processes, at 9.6%. Because a single patent record can carry multiple IPC classes, these percentages add up to more than 100%, and each should be read against the full record count rather than against one another. Adjacent areas such as catalysis, material testing, and disinfection each sit under 3%, marking them as narrower, less-crowded claim territory.
US11892393B2, assigned to A. O. Smith Corporation and published 2024-02-06, covers a water treatment system that pairs a treatment module such as a reverse osmosis unit with an electrochemical contaminant detection system placed in the waste water stream. The claimed system measures contaminant concentration and water quality parameters in the waste stream and uses a processor algorithm to back-calculate contaminant concentration in the feed water. Anyone building sensor-integrated treatment systems that infer feed-water quality from waste-stream measurements should review this claim scope directly rather than assuming it only touches sensing or only touches treatment.
The evidence points away from the core C02F and B01D classes, which already carry the largest share of records, and toward narrower cross-class areas such as real-time contaminant sensing paired with treatment modules, membrane fouling prediction, and disinfection byproduct monitoring. These sit at low single-digit shares of the record base individually. Co-assignee collaboration is also limited across the dataset, with only 10 identified pairs, suggesting joint-filing partnerships are themselves an underused strategy rather than a saturated one.
Research Environmental & Water Treatment Patent Landscape in depth with Eureka
Go past this page: query the whole environmental & water treatment patent landscape corpus yourself, in your own scope.
Every answer comes back with patent numbers you can open.
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.