CPC technology class · C23
C23G — Cleaning OR De-greasing OF Metallic Material BY Chemical…
Cleaning or de-greasing of metallic material by chemical methods other than electrolysis. 703 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.
- 703
- US patents granted
- C23
- Parent CPC class
- 20
- Active assignees
- +46%
- 5-yr velocity
CPC subclass C23G — CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS — covers 703 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class C23 (COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTAT), 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 C23G 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 C23G is shaped by 20 distinct companies actively filing in this space. NIPPON STEEL CORPORATION leads with 41 patents, followed by JFE Steel Corporation at 1,443 grants and POSCO CO., LTD at 691. 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 C23G 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 C23G innovation accelerating?
US utility-patent grants per year in C23G, 2015–2025 — recent five years are up 46% versus 2015–2019.
Who leads C23G?
The 12 most active assignees in CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS — wider bars mean more grants
- Nippon Steel
NIPPON STEEL CORPORATION
1,289 patents
- Jfe Steel
JFE Steel Corporation
1,443 patents
- Posco
POSCO CO., LTD
691 patents
- Arcelormittal 366
ArcelorMittal
366 patents
- Fujifilm Materials U 106
Fujifilm Electronic Materials U.S.A., Inc.
106 patents
- Fluid Energy Group 32
FLUID ENERGY GROUP LTD.
32 patents
- Chemetall 85
CHEMETALL GMBH
85 patents
- Primetals Japan 48
PRIMETALS TECHNOLOGIES JAPAN, LTD.
48 patents
- Biomet 3i 100
Biomet 3i, LLC
100 patents
- Toyo Kohan 94
TOYO KOHAN CO., LTD.
94 patents
- Hyundai Steel 75
Hyundai Steel Company
75 patents
- Dorf Ketal Chemicals… 29
DORF KETAL CHEMICALS FZE
29 patents
What this shows Nippon Steel is the most active filer in C23G, holding 41 of the 703 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 C23G |
|---|---|---|
| #1 | NIPPON STEEL CORPORATION | 1,289 |
| #2 | JFE Steel Corporation | 1,443 |
| #3 | POSCO CO., LTD | 691 |
| #4 | ArcelorMittal | 366 |
| #5 | Fujifilm Electronic Materials U.S.A., Inc. | 106 |
| #6 | FLUID ENERGY GROUP LTD. | 32 |
| #7 | CHEMETALL GMBH | 85 |
| #8 | PRIMETALS TECHNOLOGIES JAPAN, LTD. | 48 |
| #9 | Biomet 3i, LLC | 100 |
| #10 | TOYO KOHAN CO., LTD. | 94 |
| #11 | Hyundai Steel Company | 75 |
| #12 | DORF KETAL CHEMICALS FZE | 29 |
| #13 | NIPPON STEEL STAINLESS STEEL CORPORATION | 26 |
| #14 | ORGANO CORPORATION | 62 |
| #15 | ADVANCED TECHNOLOGY & MATERIALS CO., LTD. | 33 |
| #16 | IHI MACHINERY AND FURNACE CO., LTD. | 22 |
| #17 | Green Products & Technologies, LLC | 16 |
| #18 | HOUGHTON TECHNICAL CORP. | 11 |
| #19 | PRC-DESOTO INTERNATIONAL, INC. | 105 |
| #20 | Hydro Aluminum Rolled Products GmbH | 32 |
About This Class
CPC subclass C23G belongs to class C23.
703 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 C23G?
How many patents have been filed in C23G?
Which company holds the most patents in C23G?
How is patent data for C23G 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.