CPC technology class · C22
C22B — Production AND Refining OF Metals
Production and refining of metals ; pretreatment of raw materials. 3,163 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.
- 3,163
- US patents granted
- C22
- Parent CPC class
- 20
- Active assignees
- +7%
- 5-yr velocity
CPC subclass C22B — PRODUCTION AND REFINING OF METALS ; PRETREATMENT OF RAW MATERIALS — covers 3,163 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class C22 (METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS), 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 C22B 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 C22B is shaped by 20 distinct companies actively filing in this space. SUMITOMO METAL MINING CO., LTD. leads with 110 patents, followed by OUTOTEC (FINLAND) OY at 174 grants and FREEPORT MINERALS CORPORATION at 55. 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 C22B 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 C22B innovation accelerating?
US utility-patent grants per year in C22B, 2015–2025 — recent five years are up 7% versus 2015–2019.
Who leads C22B?
The 12 most active assignees in PRODUCTION AND REFINING OF METALS ; PRETREATMENT OF RAW MATERIALS — wider bars mean more grants
- Sumitomo Metal Mining
SUMITOMO METAL MINING CO., LTD.
511 patents
- Outotec (Finland) Oy 174
OUTOTEC (FINLAND) OY
174 patents
- Freeport Minerals 55
FREEPORT MINERALS CORPORATION
55 patents
- Jx Nippon Mining & Me…
JX Nippon Mining & Metals Corporation
350 patents
- Molten Metal Equipmen… 81
Molten Metal Equipment Innovations, LLC
81 patents
- Outotec Oyj 54
Outotec Oyj
54 patents
- Guangdong Brunp Recyc… 79
GUANGDONG BRUNP RECYCLING TECHNOLOGY CO., LTD.
79 patents
- Carbon Technology Hol… 57
Carbon Technology Holdings, LLC
57 patents
- Hunan Brunp Recycling… 77
HUNAN BRUNP RECYCLING TECHNOLOGY CO., LTD.
77 patents
- Vale 68
VALE S.A.
68 patents
- Korea Institute Of Ge… 153
Korea Institute Of Geoscience And Mineral Resources
153 patents
- Umicore 138
UMICORE
138 patents
What this shows Sumitomo Metal Mining is the most active filer in C22B, holding 110 of the 3,163 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 C22B |
|---|---|---|
| #1 | SUMITOMO METAL MINING CO., LTD. | 511 |
| #2 | OUTOTEC (FINLAND) OY | 174 |
| #3 | FREEPORT MINERALS CORPORATION | 55 |
| #4 | JX Nippon Mining & Metals Corporation | 350 |
| #5 | Molten Metal Equipment Innovations, LLC | 81 |
| #6 | Outotec Oyj | 54 |
| #7 | GUANGDONG BRUNP RECYCLING TECHNOLOGY CO., LTD. | 79 |
| #8 | Carbon Technology Holdings, LLC | 57 |
| #9 | HUNAN BRUNP RECYCLING TECHNOLOGY CO., LTD. | 77 |
| #10 | VALE S.A. | 68 |
| #11 | Korea Institute Of Geoscience And Mineral Resources | 153 |
| #12 | UMICORE | 138 |
| #13 | CIDRA CORPORATE SERVICES LLC | 92 |
| #14 | GEM CO., LTD. | 41 |
| #15 | BEIJING UNIVERSITY OF TECHNOLOGY | 175 |
| #16 | PYROTEK, INC. | 50 |
| #17 | LILAC SOLUTIONS, INC. | 26 |
| #18 | HERAEUS DEUTSCHLAND GMBH & CO. KG | 205 |
| #19 | Worcester Polytechnic Institute | 150 |
| #20 | TECHNOLOGICAL RESOURCES PTY LIMITED | 76 |
About This Class
CPC subclass C22B belongs to class C22.
3,163 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 C22B?
How many patents have been filed in C22B?
Which company holds the most patents in C22B?
How is patent data for C22B 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.