CPC technology class · C23
C23C — Coating Metallic Material
Coating metallic material; coating material with metallic material; surface treatment of metallic material by diffusion into the surface, by chemical conversion or substitution; coating by vacuum evaporation, by sputtering, by ion implantation or by chemical vapour deposition, in general. 29,488 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.
- 29,488
- US patents granted
- C23
- Parent CPC class
- 20
- Active assignees
- +18%
- 5-yr velocity
CPC subclass C23C — COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL — covers 29,488 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 C23C 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 C23C is shaped by 20 distinct companies actively filing in this space. Applied Materials, Inc. leads with 2,196 patents, followed by TOKYO ELECTRON LIMITED at 5,061 grants and ASM IP Holding B.V. at 1,116. 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 C23C 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 C23C innovation accelerating?
US utility-patent grants per year in C23C, 2015–2025 — recent five years are up 18% versus 2015–2019.
Who leads C23C?
The 12 most active assignees in COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL — wider bars mean more grants
- Applied Materials 6,997
Applied Materials, Inc.
6,997 patents
- Tokyo Electron 5,061
TOKYO ELECTRON LIMITED
5,061 patents
- Asm Ip Holding B V 1,116
ASM IP Holding B.V.
1,116 patents
- Lam Research 1,965
Lam Research Corporation
1,965 patents
- Taiwan Semiconductor…
TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
31,041 patents
- Jfe Steel 1,443
JFE Steel Corporation
1,443 patents
- Kokusai Electric 587
Kokusai Electric Corporation
587 patents
- Nippon Steel 1,289
NIPPON STEEL CORPORATION
1,289 patents
- Hitachi Kokusai Elect… 618
HITACHI KOKUSAI ELECTRIC INC.
618 patents
- Boe Technology Group
BOE Technology Group Co., Ltd.
18,263 patents
- Posco 691
POSCO CO., LTD
691 patents
- Nippon Steel & Sumito… 842
NIPPON STEEL & SUMITOMO METAL CORPORATION
842 patents
What this shows Applied Materials is the most active filer in C23C, holding 2,196 of the 29,488 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 C23C |
|---|---|---|
| #1 | Applied Materials, Inc. | 6,997 |
| #2 | TOKYO ELECTRON LIMITED | 5,061 |
| #3 | ASM IP Holding B.V. | 1,116 |
| #4 | Lam Research Corporation | 1,965 |
| #5 | TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD. | 31,041 |
| #6 | JFE Steel Corporation | 1,443 |
| #7 | Kokusai Electric Corporation | 587 |
| #8 | NIPPON STEEL CORPORATION | 1,289 |
| #9 | HITACHI KOKUSAI ELECTRIC INC. | 618 |
| #10 | BOE Technology Group Co., Ltd. | 18,263 |
| #11 | POSCO CO., LTD | 691 |
| #12 | NIPPON STEEL & SUMITOMO METAL CORPORATION | 842 |
| #13 | ArcelorMittal | 366 |
| #14 | UNITED TECHNOLOGIES CORPORATION | 4,091 |
| #15 | JX Nippon Mining & Metals Corporation | 350 |
| #16 | Sumitomo Electric Industries, Ltd. | 4,378 |
| #17 | Oerlikon Surface Solutions AG, Pfäffikon | 168 |
| #18 | MITSUBISHI MATERIALS CORPORATION | 640 |
| #19 | RAYTHEON TECHNOLOGIES CORPORATION | 2,501 |
| #20 | SUMITOMO ELECTRIC HARDMETAL CORP. | 459 |
About This Class
CPC subclass C23C belongs to class C23.
29,488 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 C23C?
How many patents have been filed in C23C?
Which company holds the most patents in C23C?
How is patent data for C23C collected?
What is the difference between CPC class and subclass?
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Explore the patent dataset
Read our methodology — how this data is sourced, computed, and verified.