TFC RO Membrane Patents: Top Companies & Filing Trends 2026
Thin-Film-Composite Reverse-Osmosis Membrane Patents: Who Leads and Where the Field Is Still Open
Concentrated but not locked up. the ranked leader holds 1,344 records, yet the top 5 combined are only 21.7% of all 13,521 records in scope. Filings peaked at 575 in 2017 and have declined since; 2021 stood at 380 and 2024 at 311, an 18% drop over that three-year window. Treat 2025 and 2026 figures as incomplete rather than as evidence of a further slide, since publication lag has not yet caught up.
- 1TORAY INDUSTRIES INC9.9%
- 2KURITA WATER INDUSTRIES LTD4.7%
- 3UOP LLC3.1%
- 4NITTO DENKO CORP2.7%
- 5EXXONMOBIL TECHNOLOGY & ENGINEERING CO1.4%
See the full membranes & separation polymers — thin-film-composite reverse-osmosis 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 TFC RO membrane patents
Who holds the most patents on thin-film-composite reverse-osmosis membranes?
One assignee leads the ranked field with 1,344 records, well ahead of fifth place at 183 and tenth at 136. That said, the top 5 assignees combined represent only 21.7% of the 13,521 total records in scope, and the top 10 only 27.0%, so no single company or small group controls the field outright. A freedom-to-operate review should still start with the leader’s portfolio given the size of the gap, but should not stop there.
Is patent filing for RO membranes growing or slowing down?
Filings peaked at 575 in 2017 and have generally declined since, with 2021 at 380 falling to 311 by 2024 — an 18% drop over that three-year span. Figures for 2025 and 2026 look lower still, but publication typically lags filing by around 18 months, so those recent years are undercounted rather than necessarily reflecting a real slowdown. The safest reading is that filing activity cooled after 2017 through at least 2024.
What technology areas are most contested in TFC membrane patents?
Separation-process claims under IPC class B01D appear on 63.2% of the 13,521 records, and water/wastewater treatment under C02F appears on 33.0%, making these the most heavily claimed areas. Polymer-synthesis-focused classes such as C08G (condensation polymers, 4.4%) and C08J (polymer processing, 5.5%) see far less filing density, which is worth noting since a record can carry multiple IPC codes. Anyone drafting new claims in the core separation-membrane space should expect dense prior art there.
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 — Thin-Film-Composite Reverse-Osmosis 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.