Heavy Metal Chelating Precipitants Patents: Leaders & Trends 2026
- Concentrated at the top. The five leading assignees hold 54.1% of all 222 records in scope, and the top ten hold 64.0% — a long tail of single- or few-filing entrants fills the rest of the ranked field.
- Filing has plateaued, not grown. Volume moved from 3 filings in 2021 to 3 in 2024, a flat 0% over that span, after peaking at 13 filings in 2017.
- Wastewater treatment dominates the class mix. C02F covers 73.0% of the 222 records, more than double the next most common subclass, C01F at 29.7%.
Filing growth compares 2021 (3 records) with 2024 (3) — 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 222 records in scope (CR5), not by the ranked leaders only.
What this landscape covers
Heavy metal chelating precipitants are the chemistries — dithiocarbamates, sulfide-donor reagents and related organic and inorganic complexing agents — used to pull dissolved copper, lead, mercury, cadmium and similar metals out of effluent as a stable, low-solubility solid. The 222 records in this dataset span filings from 2015 through the 2026-07-31 cut-off and cluster around three practical questions: how selective a precipitant is across a given pH window, how it performs against already-complexed copper rather than free ions, and how much sludge volume the resulting solid leaves behind for disposal.
Because publication trails filing by roughly 18 months, the 2025 and 2026 counts in the trend chart are undercounts by construction, not evidence of a slowdown — read the 2024 figure as the last complete year.
Filing trend and technology composition
Two views of the same 222 records: how filing activity has moved year over year, and how those records distribute across IPC subclasses.
Filing trend, 2017–2026
Filings peaked at 13 in 2017 and have since settled into a lower, flatter band — 3 filings in 2021 and 3 again in 2024, a 0% change over that three-year window. Treat 2025 and 2026 as still filling in given publication lag.
Technology composition by IPC subclass
C02F (water and wastewater treatment) appears on 73.0% of the 222 records, far ahead of C01F (alkaline-earth, aluminium and rare-earth compounds) at 29.7% and C01B (non-metallic elements and inorganic compounds) at 17.1%. Fertiliser-adjacent classes C05B and C05F each sit near 15%, pointing to a recurring overlap between metal-precipitation chemistry and nutrient-recovery byproduct streams.
Shares are the percentage of the 222 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Heavy Metal Chelating Precipitants with Eureka
This page is one run against one query. Ask Eureka your own question about heavy metal chelating precipitants and every answer comes back with the patent numbers behind it.
Try EurekaMost-cited records and a representative filing
Dendritic polymer heavy metal precipitant with double functions of chelation and self-flocculation
A dithiocarbamate-terminated polyamidoamine dendritic polymer (PAMAM generation 1-3) combines chelation and self-flocculation in one molecule. The branched structure and high density of terminal dithiocarbamate groups give it strong chelating affinity for heavy metals alongside a flocculation function that a conventional linear chelating precipitant does not provide.Filed by Tongji University, published 2018-08-02.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US20050258103A1 | Methods for removing heavy metals from water using chemical precipitation and field separation methods | 96 |
| 2 | US7255793B2 | Methods for removing heavy metals from water using chemical precipitation and field separation methods | 73 |
| 3 | US20110174743A1 | Hybrid composites for contaminated fluid treatment | 70 |
| 4 | US6896815B2 | Methods for removing heavy metals from water using chemical precipitation and field separation methods | 69 |
| 5 | US20030082084A1 | Methods for removing heavy metals from water using chemical precipitation and field separation methods | 62 |
| 6 | US20080135491A1 | Methods from removing heavy metals from water using chemical precipitation and field separation methods | 48 |
| 7 | US6066256A | Biological solubilization process for converting contaminated sludge into enriched biosolids | 48 |
| 8 | US20020003112A1 | Process and apparatus for removal of heavy metals from wastewater | 47 |
| 9 | US5770090A | Method for recovery of heavy metal from waste water | 43 |
| 10 | US20140124447A1 | Formulations and methods for removing heavy metals from waste solutions containing chelating agents | 41 |
Citation counts favour older filings that have had more time to accumulate citations inside this corpus — read them as a signal of influence on the field, not 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 mean for a filing decision
Three patterns matter more than the raw counts: where claim density sits, where growth has actually gone, and which jurisdictions carry the bulk of enforceable rights.
Leadership is narrow, the tail is long
The five leading assignees hold 120 of the 222 records in scope — 54.1% — while the ranked field runs to 74 companies. Most of that tail files once or twice, which usually means a specific formulation or a single plant application rather than a platform claim.
Flat, not declining
Filing volume moved from 3 records in 2021 to 3 in 2024 — a flat trend after the 2017 peak of 13. That reads as a mature, steady-state filing rate rather than either an expansion or a retreat from the space.
US anchors the filing map, PCT signals global intent
The United States receives the largest single share of filings at 63, with WIPO's PCT route (18) and India (17) next. The PCT count indicates a meaningful minority of applicants are pursuing multi-jurisdiction protection rather than filing domestically only.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to heavy metal chelating precipitants, with the prior art for and against each one.
Who is filing, and where the openings sit
The ranked field spans large industrial operators, university labs and single-invention filers. Co-assignee activity is sparse, which suggests most work here is done in-house rather than through joint filings.
One assignee well ahead of the pack
The leading assignee holds 76 records, well clear of fifth place at 5 and tenth place at 4 — a gap that marks a genuine outlier rather than a gradual taper.
Joint filing is rare
Only five co-assignee pairs appear across the dataset, each linked by two shared records. That pattern points to filings built around individual inventors attached to a single corporate assignee rather than cross-company R&D partnerships.
Universities file steadily but not in volume
Research institutions appear throughout the ranked list but at low per-entity counts, consistent with a field where academic labs patent specific chemistries rather than building broad platform portfolios.
| Assignee | Recent year | YoY |
|---|---|---|
| EasyMining Sweden AB | 0 | — |
| Texas A&M University | 0 | — |
| Massachusetts Institute of Technology | 0 | — |
| Drinkard Metalox Inc. | 0 | — |
| National University of Singapore | 0 | — |
| CORT STEVEN L | 0 | — |
| AKS IND AUSTRALIA PTY LTD | 0 | — |
| Ionics Inc. | 0 | — |
Where to take this analysis
The dataset points to a stable but concentrated field with specific technical gaps still open. Two directions are worth pursuing next.
Map the leader's claim boundaries
With one assignee holding 76 of 222 records, understanding exactly which pH ranges, metal species and formulation classes its claims cover is the first step before filing anywhere near its core chemistry.
Explore assignee claim scope in EurekaTest the white-space chips against full claim text
The under-claimed branches identified here are based on class-level filing density; confirming they are genuinely open requires reading independent claim language against them.
Run a freedom-to-operate check in EurekaCommon questions on this landscape
One assignee leads the ranked field with 76 of the 222 records in scope, a wide margin ahead of fifth place at 5 records and tenth place at 4. The remaining 74 ranked assignees form a long tail of small-volume filers, many with only one or two records, typically tied to a specific formulation or application rather than a broad platform. This concentration means competitive freedom-to-operate analysis should start with the leader's claims before looking at the tail.
Filing activity peaked at 13 records in 2017 and has since settled into a lower, flat pattern, with 3 filings in 2021 and 3 in 2024 — a 0% change over that span. This reads as a mature, steady-state technology area rather than one in active expansion or decline. Figures for 2025 and 2026 are still incomplete because publication typically lags filing by around 18 months, so recent years should not be read as a drop-off.
C02F, covering water and wastewater treatment, appears on 73.0% of the 222 records and is by far the dominant class. But a meaningful share also touches fertiliser-related classes — C05B (phosphate fertilisers) at 15.3% and C05F (organic and waste-derived fertilisers) at 14.4% — reflecting overlap between metal-precipitation chemistry and byproduct or nutrient-recovery streams. Separation processes (B01D, 14.9%) and various inorganic compound classes (C01B, C01D, C01G) also recur, indicating the chemistry crosses several adjacent industrial uses.
The United States is the leading receiving office with 63 filings, followed by the WIPO PCT route at 18 and India at 17. Europe (EPO) accounts for 16, Australia for 14 and Canada for 9. The PCT share indicates that a portion of applicants are seeking multi-jurisdiction coverage rather than filing only in a home market, which is worth checking when assessing where a given assignee's rights are actually enforceable.
Filing density is heavily weighted toward core wastewater-treatment claims (C02F), which leaves several adjacent, more specific branches thinner: selective capture across variable pH windows, precipitants targeting already-complexed copper rather than free metal ions, and formulations designed explicitly to minimise resulting sludge volume. Self-flocculating dithiocarbamate polymer chemistry, as seen in one representative 2018 filing, is another area with limited surrounding claim density. Confirming these gaps requires reading independent claims directly, since class-level composition only indicates where filing volume is thin, not where claims are absent.
Research Heavy Metal Chelating Precipitants in depth with Eureka
Go past this page: query the whole heavy metal chelating precipitants 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.