FO Membrane Surface Engineering Patent Landscape 2026
The FO membrane surface engineering field is moderately concentrated, with Asahi Kasei holding a commanding lead over a mix of industrial and academic challengers. Annual filing volume has eased from its 2019 peak, signaling a maturing field where differentiation on surface chemistry and application breadth is increasingly decisive.
Asahi Kasei dominates a moderately concentrated field
Asahi Kasei Kogyo Kabushiki Kaisha leads the ranking by a wide margin, followed by LG NanoH2O, Oasys Water, Porifera, and Toray Advanced Materials Korea — all of which are meaningfully separated from the leader in patent records.
The top five filers account for 38% of the hundred largest filers’ combined total, indicating moderate concentration: the leader holds a clear structural advantage, but the second tier is populated by multiple credible industrial and academic entities, leaving room for challengers to carve out positions.
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 1 | Asahi Kasei Kogyo Kabushiki Kaisha | 92 | |
| 2 | LG NanoH2O Inc | 26 | |
| 3 | Oasys Water Inc | 24 | |
| 4 | Porifera Inc | 23 | |
| 5 | Toray Advanced Materials Korea Inc | 23 | |
| 6 | National University of Singapore | 22 | |
| 7 | Gradiant Corp | 14 | |
| 8 | LG Chem Ltd | 14 | |
| 9 | Diamond Gold Investors LLC | 12 | |
| 10 | Kobe University | 12 |
| # | Applicant | Patent records | Share |
|---|---|---|---|
| 11 | Nanyang Technological University | 9 | |
| 12 | NanoH2O Co Ltd | 8 | |
| 13 | Beijing Baoshengtong International Electric Engineering Technology Co Ltd | 8 | |
| 14 | San Jose State University Research Foundation | 7 | |
| 15 | EAST CHINA UNIV OF SCI & TECH | 7 | |
| 16 | Xi’an University of Architecture and Technology | 7 | |
| 17 | IBM Corporation | 7 | |
| 18 | Zhejiang University of Technology | 6 | |
| 19 | National Tsing Hua University | 6 | |
| 20 | KOREA UNIV RES & BUSINESS FOUND | 6 |
Asahi Kasei’s scale implies deep freedom-to-operate risk in core membrane separation classes; entrants and challengers should map their surface-engineering approach against the leader’s densely filed B01D sub-classes before committing R&D resources.
The most recent 18–24 months of filing data are subject to publication lag and are likely under-counted; apparent low activity in 2024–2026 should not be interpreted as a further acceleration of decline. Longer-window growth, applicant concentration, and technology-route coverage are therefore more reliable signals than the latest-year bar alone.
Filing volume has eased from a 2019 peak; separation-process classes dominate the technology mix
The annual filing trend and technology composition charts together reveal a field that reached its highest annual activity around 2019 and has since moderated, while remaining firmly anchored in membrane separation and water-treatment classes with only sparse activity in adjacent branches.
Annual filing trend
Filing activity peaked in 2019 and has since eased, with 2024–2026 counts suppressed by publication lag and not yet reliable. The multi-year pattern confirms a post-peak trajectory rather than a short-term fluctuation.
↗ Hover for values · click a bar to ask EurekaTechnology composition
B01D (Separation processes) dominates the technology mix by a large margin, followed at a distance by C02F (Water & wastewater treatment). Application-specific classes such as A23L (Foods & beverages), B05D (Coating processes), and C08G (Condensation polymers) each carry only a small share, pointing to under-served branches adjacent to the core.
↗ Hover for values · click a bar to ask EurekaHighly cited patent families surfaced by the query
Citation-heavy patent families returned by the query. Use this section as citation context, not as a curated list of the most topic-specific patents.
Method for manufacturing membrane using selective …
The present invention relates to a method for manufacturing a composite membrane using a selective layer prepared through the interfacial polymerization (support-free interfacial polymerization) on a free interface without a support and, more specifically, to a method for manufacturing a composite membrane comprising a reverse osmotic membrane, which is… (excerpt from the patent abstract)
| # | Patent | Citations |
|---|---|---|
| 1 | Osmotic membrane synthesized on interface | 147 |
| 2 | A forward osmosis membrane | 109 |
| 3 | Thin film composite membranes for forward osmosis,… | 101 |
| 4 | Forward osmosis membrane for seawater desalination… | 69 |
| 5 | High Flux Thin-Film Composite Forward Osmosis and … | 66 |
| 6 | Forward osmosis membranes | 52 |
| 7 | Forward osmosis membranes | 46 |
| 8 | Nanoparticle-functionalized membranes, methods of … | 44 |
Ranked by total forward citations. Citation counts favour older and broadly cited patent families, and broad or adjacent patents may appear when they match the search scope. Treat this section as citation context, not as a curated list of the most topic-specific patents. Some patent titles may be shown in their original, non-English language where an accurate translation could not be guaranteed.
What the competitive structure means for R&D investment decisions
Four structural reads — maturity, concentration, collaboration patterns, and geographic spread — each carry distinct implications for teams deciding where and how to enter or deepen positions in FO membrane surface engineering.
Declining phase: annual volume has eased from the 2019 peak
The lifecycle stage is classified as Decline, with annual filings easing back from the 2019 peak and a recent-window growth rate of –22%. This does not mean the technology is obsolete; it signals that foundational surface-engineering approaches are well-documented, and incremental claims in core separation classes face a dense prior-art landscape. R&D investment is most defensible in differentiated sub-areas or novel application contexts.
Post-peak · 2019 highModerate concentration with a pronounced leader-challenger gap
Asahi Kasei’s 92 patent records place it well ahead of the next tier (LG NanoH2O at 26, Oasys Water at 24, Porifera and Toray Advanced Materials Korea each at 23). The top five control 38% of the hundred largest filers’ combined total. A challenger strategy focused on distinct surface-modification chemistries or niche application verticals is more viable than a direct assault on Asahi Kasei’s core B01D positions.
Top-5 share: 38%Strategic partnerships anchor the second tier
The most active co-filing pair is LG NanoH2O and LG Chem, with 21 jointly filed records, reflecting a vertically integrated R&D effort within the LG group. National University of Singapore and BASF are the second most active pair at 14 joint records, bridging academic membrane research with industrial chemistry. Asahi Kasei and Kobe University have 12 jointly filed records, pairing industrial scale with university polymer expertise. These relationships suggest that university-industry alliances are a productive entry path for organizations seeking to build positions without a large in-house patent portfolio.
Top pair: LG NanoH2O–LG Chem (21)US and China are co-equal filing destinations; PCT coverage is meaningful
The United States and China each attract approximately 100 patent records, making them the co-dominant jurisdictions for FO membrane surface engineering. Europe (EPO) and WIPO (PCT) add significant reach, and South Korea, Australia, and Canada each carry notable counts. Singapore, where the National University of Singapore is a leading academic filer, also appears. This broad multi-jurisdiction footprint reflects the global commercial relevance of desalination and water-treatment markets.
Lead offices: US & ChinaGo beyond the landscape: Eureka’s TRIZ Solution agent breaks down an R&D problem and returns patented concept solutions, each with a technical approach and cited patent & literature evidence.
| Applicant | Collaborator | Co-filings |
|---|---|---|
| LG NanoH2O Inc | LG Chem Ltd | 21 |
| National University of Singapore | BASF SE | 14 |
| Asahi Kasei Corporation | Kobe University | 12 |
| National University of Singapore | Kraton Polymers US LLC | 3 |
| National University of Singapore | BASF SCHWEIZ AG | 1 |
| BASF SE | BASF SCHWEIZ AG | 1 |
Co-filing pairs, ranked by the number of jointly-filed patent families.
Asahi Kasei leads in scale; LG NanoH2O anchors the industrial challenger tier
The two largest industrial players share an orientation toward core B01D separation-process classes but differ in scale, trajectory, and collaborative strategy. Both matter for freedom-to-operate analysis in thin-film composite and membrane-structure engineering.
Asahi Kasei
Asahi Kasei Kogyo holds 92 patent records — more than three times the next-ranked applicant — concentrated across B01D membrane-structure, polymer-type, and separation-process sub-classes. Its applicant momentum shows a recent-period trend of –39%, indicating that the company’s filing pace has moderated from earlier highs, consistent with the field-wide post-peak pattern. Despite the deceleration, its accumulated portfolio presents the densest prior-art barrier in the space.
Patent records: 92LG NanoH2O
LG NanoH2O holds 26 patent records, with technology emphasis on B01D polymer-type and membrane-structure classes closely mirroring the leader’s profile but at roughly one-quarter the depth. The company’s co-filing relationship with parent LG Chem (21 joint records) extends effective portfolio breadth into condensation-polymer and process chemistry territory. This integrated position within the LG group distinguishes it from purely independent challengers such as Oasys Water and Porifera.
Patent records: 26| Applicant | Recent (3 yrs) | Trend |
|---|---|---|
| Asahi Kasei Corporation | 23 | ▼ -39% |
Under-served branches adjacent to core FO membrane classes
Several IPC classes appear in the corpus at low share relative to the dominant B01D anchor, representing areas where FO membrane surface engineering intersects other disciplines with limited dedicated prior art. These are observations of relative sparsity; technical and commercial value requires further validation.
A23L · Foods & Non-Alcoholic Beverages
With 21 patent records and a 3% share of the technology composition, A23L is the largest of the sparse adjacent branches. FO membranes have documented utility in juice concentration, dairy processing, and flavor preservation, where osmotic driving force avoids thermal degradation. The prior-art density here is low relative to B01D, and established food-processing players have not prominently appeared in this corpus’s applicant ranking — creating a plausible entry path for membrane developers with food-grade surface-modification capabilities.
Search this in Eureka →B05D · Coating Processes
B05D appears with 12 patent records and a 2% share, reflecting that coating-process methodologies for applying functional layers to FO membranes are under-patented relative to the membrane structures themselves. As surface engineering increasingly involves atomic-layer deposition, spray coating, and layer-by-layer assembly, explicit B05D claims could provide orthogonal protection not captured by B01D filings. The sparse prior art here warrants investigation for applicants developing scalable surface-functionalization manufacturing steps.
Search this in Eureka →Frequently asked questions
The corpus covers 233 patent families in FO membrane surface engineering, drawn from filings across major global patent offices.
Asahi Kasei Kogyo Kabushiki Kaisha leads with 92 patent records, more than three times the next-ranked applicant. Its portfolio is concentrated in B01D separation-process sub-classes covering membrane structure and polymer type.
No. The field is classified as Decline: annual filings peaked in 2019 and have eased since, with a recent-window growth rate of -22%. The most recent 18–24 months are subject to publication lag and are under-counted, so the apparent 2024–2026 low should not be over-interpreted.
The United States and China each attract approximately 100 patent records, making them co-equal primary filing destinations. Europe (EPO) and WIPO (PCT) add significant coverage, followed by South Korea, Australia, and Canada.
LG NanoH2O and LG Chem are the most active pair with 21 jointly filed records. National University of Singapore and BASF follow with 14 joint records, and Asahi Kasei and Kobe University have 12 jointly filed records.
The sparsest notable branches relative to the dominant B01D core are A23L (Foods & non-alcoholic beverages, 21 records, 3% share) and B05D (Coating processes, 12 records, 2% share). C08G (Condensation polymers), B32B (Layered products & laminates), and D01D (Man-made filament spinning) each hold roughly 1% share, suggesting limited dedicated prior art in those areas.
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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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