Ion-Exchange Membrane Patents: Leaders, Trends & White Space 2026
Ion-Exchange Polymer Membrane Patents: Who Leads and Where the Claim Space Is Still Open
Concentration is modest at the top. the leading five assignees together hold just 9.2% of all 13,779 records in scope, and the leading ten hold 15.5% — this is not a field with a single gatekeeper. Filings ran from 387 in 2017 to a peak of 727 in 2023, with 2021-to-2024 volume up 13% (492 to 557). The 2025-2026 dip is a publication-lag artefact, not a real contraction — those years are still being filled in as later-filed applications publish.
- 1EVOQUA WATER TECHNOLOGIES LLC2.5%
- 2TOKUYAMA CORP1.8%
- 3EI DU PONT DE NEMOURS & CO1.7%
- 4AGC INC1.6%
- 5TITI ELLEBEAU INC1.6%
See the full membranes & separation polymers — ion-exchange polymer membranes patent landscape analysis in Eureka
- The complete ranking, not just the top five
- Every IPC branch with its share of the corpus
- The most-cited records, and where claim space is still thin
Common questions about this landscape
Who holds the most ion-exchange membrane patents?
The dataset ranks 100 assignees, and the leading company holds 345 of the 13,779 records in scope, well ahead of fifth place at 216. That said, the top five assignees combined hold only 9.2% of all records, so no single company dominates the field the way a single-leader narrative might suggest. The remaining records are spread across a long tail of companies with far fewer filings each, which matters for freedom-to-operate analysis since most of the field sits outside the leaders’ core claims.
Is the number of ion-exchange membrane patent filings still growing?
Yes, over the most recent complete filing years: annual counts rose from 492 in 2021 to 557 in 2024, a 13% increase, with a peak of 727 in 2023. Figures for 2025 and 2026 look lower in the raw trend chart, but that reflects publication lag — patent applications typically publish around 18 months after filing, so the newest years are still being backfilled rather than showing a genuine slowdown. Anyone using this trend to justify a filing timeline should treat the last one to two years as incomplete.
What technology areas do ion-exchange membrane patents actually cover?
The heaviest overlap is with energy applications: 35.3% of the 13,779 records carry an H01M classification (batteries, cells and fuel cells) and 26.8% carry C25B (electrolytic production of compounds). Classic separation-process claims (B01D) sit close behind at 26.0%, with water and wastewater treatment (C02F) at 14.2%. Because a single patent can carry multiple IPC codes, these percentages overlap rather than summing to 100%, which is expected given how often membrane patents claim both a material and a downstream application.
Disclaimer. This analysis is based on Patsnap Eureka data drawn from a limited snapshot of global patent records and is provided for general information and reference only. Patent data carries inherent limitations — recent filings are under-counted because of publication lag, counts may be on a record or family basis, classification and applicant-name data may contain errors or duplicates, and the underlying search query defines the scope shown — so the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing here is an exhaustive prior-art, novelty, freedom-to-operate or validity search, nor does it constitute legal, financial or professional advice, and it should not be relied upon as such. Verify independently and review with qualified patent and legal professionals before acting on it.
Method: Filing trend and technology composition. Derived from a Patsnap search on Membranes & Separation Polymers — Ion-Exchange Polymer Membranes Patent Landscape covering 2015–2026, data cut-off 2026-07-31. Counts reflect published records only and shift as new filings publish. Every share divides by all records in scope. Data: Patsnap Eureka. See the full landscape report.