Combined Sewer Overflow Patents: Leaders, Trends & White Space 2026
Combined Sewer Overflow Control Patents: Who Files, What They Claim, Where the Gaps Sit
Concentrated at the top. The top 5 assignees hold 58.1% of all 62 records in scope, and the top 10 hold 82.3% — a short list of repeat filers controls most of the documented claim space. Filings rose from 3 records in 2017 to a peak of 7 in 2018, then declined; the 2021-to-2024 span shows a -100% change, and the leading assignees each show 0 filings in the latest year. Because publication typically lags filing by around 18 months, the last one to two years in any trend chart will always look thinner than the true filing rate — treat the most recent years as provisional, not as evidence of a stalled field.
- 1GHALIB SAAD A13
- 2EBARA CORP8
- 3RTC4WATER SARL7
- 4OPTIRTC4
- 5OVIVO WATER INC4
See the full combined sewer overflow control 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 on CSO control patents
Who holds the most patents in combined sewer overflow control?
The ranking covers 19 assignees across 62 records, and it is led by a single assignee with 13 records, well ahead of fifth place at 4. The top 5 assignees together hold 58.1% of all 62 records, and the top 10 hold 82.3%, so filing activity is concentrated rather than evenly spread. Anyone assessing this space should treat that leading group as the primary prior-art risk rather than assuming the field is fragmented.
Is patent filing in CSO control growing or slowing down?
Filing peaked at 7 records in 2018 and has since declined, with a -100% change recorded between 2021 and 2024. However, publication typically lags filing by around 18 months, so the most recent one to two years in any dataset will always understate true filing activity. The honest read is that the field has cooled from its 2018 high, not that it has stopped — later years need time to finish publishing before a firm conclusion is possible.
What technology areas do CSO control patents actually cover?
Based on IPC classification of the 62 records, 71.0% carry C02F (water and wastewater treatment) codes and 29.0% carry E03F (sewerage) codes, meaning treatment technology is claimed far more often than sewer infrastructure itself. Smaller shares cover digital data processing (19.4%), control and regulating systems (14.5%), and biocide-related treatment (12.9%). Because records can carry multiple classes, these figures describe overlapping technical content rather than a clean split of the field.
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 Combined Sewer Overflow Control 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.