CPC technology class · C02
C02F — Treatment OF Water
Treatment of water, waste water, sewage, or sludge. 14,501 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.
- 14,501
- US patents granted
- C02
- Parent CPC class
- 20
- Active assignees
- +36%
- 5-yr velocity
CPC subclass C02F — TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE — covers 14,501 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class C02 (TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE), one of roughly 250 top-level technology categories in the Cooperative Patent Classification system jointly maintained by the USPTO and the European Patent Office. At the subclass level, four-character codes like C02F give the most practical resolution for tracking a specific technology domain without losing sight of adjacent filings. Every grant here has been classified by a USPTO examiner based on the technical disclosure in the patent specification.
The competitive landscape in C02F is shaped by 20 distinct companies actively filing in this space. ECOLAB USA INC. leads with 243 patents, followed by KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS at 2,002 grants and Evoqua Water Technologies LLC at 233. Concentration at the top of the leaderboard indicates whether this technology area is dominated by a handful of incumbents or fragmented across many filers — a useful signal for investors evaluating competitive moats and for product teams mapping freedom-to-operate risk.
Filing trajectory matters as much as static counts. The yearly series on this page plots grants from 2015 through 2025, highlighting whether innovation in C02F is accelerating, plateauing, or cooling. Technology areas with rising post-2020 activity often reflect emerging markets or new platform shifts, while declining filings can signal mature domains where incremental improvement has slowed. Researchers, licensing professionals, and competitive-intelligence teams use these patterns — together with the top-assignee distribution — to decide where to invest, where to license, and where to avoid entanglement. All counts on this page come directly from USPTO PatentsView and reflect US granted utility patents only.
Is C02F innovation accelerating?
US utility-patent grants per year in C02F, 2015–2025 — recent five years are up 36% versus 2015–2019.
Who leads C02F?
The 12 most active assignees in TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE — wider bars mean more grants
- Ecolab Usa 1,610
ECOLAB USA INC.
1,610 patents
- King Fahd University… 2,002
KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS
2,002 patents
- Evoqua Water 233
Evoqua Water Technologies LLC
233 patents
- Saudi Arabian Oil
SAUDI ARABIAN OIL COMPANY
6,393 patents
- Veolia Water Solution… 102
Veolia Water Solutions & Technologies Support
102 patents
- Kurita Water Industri… 131
KURITA WATER INDUSTRIES LTD.
131 patents
- Nanjing University 255
Nanjing University
255 patents
- Kemira Oyj 230
KEMIRA OYJ
230 patents
- Tongji University 194
TONGJI UNIVERSITY
194 patents
- King Technology 66
King Technology, Inc.
66 patents
- Doosan Heavy Industri… 354
DOOSAN HEAVY INDUSTRIES & CONSTRUCTION CO., LTD.
354 patents
- King Abdulaziz Univer… 576
King Abdulaziz University
576 patents
What this shows Ecolab Usa is the most active filer in C02F, holding 243 of the 14,501 patents in this class. Concentration at the top signals how contestable this technology area is for new entrants.
View data table
| Rank | Company | Patents in C02F |
|---|---|---|
| #1 | ECOLAB USA INC. | 1,610 |
| #2 | KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS | 2,002 |
| #3 | Evoqua Water Technologies LLC | 233 |
| #4 | SAUDI ARABIAN OIL COMPANY | 6,393 |
| #5 | Veolia Water Solutions & Technologies Support | 102 |
| #6 | KURITA WATER INDUSTRIES LTD. | 131 |
| #7 | Nanjing University | 255 |
| #8 | KEMIRA OYJ | 230 |
| #9 | TONGJI UNIVERSITY | 194 |
| #10 | King Technology, Inc. | 66 |
| #11 | DOOSAN HEAVY INDUSTRIES & CONSTRUCTION CO., LTD. | 354 |
| #12 | King Abdulaziz University | 576 |
| #13 | BL TECHNOLOGIES, INC. | 109 |
| #14 | Imam Abdulrahman Bin Faisal University | 403 |
| #15 | Haier US Appliance Solutions, Inc. | 1,829 |
| #16 | KING SAUD UNIVERSITY | 622 |
| #17 | Gradiant Corporation | 44 |
| #18 | ORGANO CORPORATION | 62 |
| #19 | KING FAISAL UNIVERSITY | 803 |
| #20 | Coway Co., Ltd. | 195 |
About This Class
CPC subclass C02F belongs to class C02.
14,501 patents were granted in this class between 2015 and 2025.
20 companies actively patent in this space.
Classification System
Cooperative Patent Classification (CPC) is a hierarchical patent classification system used by the USPTO and EPO.
Frequently Asked Questions
What is CPC class C02F?
How many patents have been filed in C02F?
Which company holds the most patents in C02F?
How is patent data for C02F collected?
What is the difference between CPC class and subclass?
Learn More
Explore the patent dataset
Read our methodology — how this data is sourced, computed, and verified.