CPC technology class · C08
C08C — Treatment OR Chemical Modification OF Rubbers
Treatment or chemical modification of rubbers. 1,240 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.
- 1,240
- US patents granted
- C08
- Parent CPC class
- 20
- Active assignees
- -8%
- 5-yr velocity
CPC subclass C08C — TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS — covers 1,240 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class C08 (ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON), 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 C08C 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 C08C is shaped by 20 distinct companies actively filing in this space. BRIDGESTONE CORPORATION leads with 150 patents, followed by SUMITOMO RUBBER INDUSTRIES, LTD. at 2,232 grants and ZEON CORPORATION at 926. 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 C08C 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 C08C innovation accelerating?
US utility-patent grants per year in C08C, 2015–2025 — recent five years are down 8% versus 2015–2019.
Who leads C08C?
The 12 most active assignees in TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS — wider bars mean more grants
- Bridgestone
BRIDGESTONE CORPORATION
1,895 patents
- Sumitomo Rubber Indus…
SUMITOMO RUBBER INDUSTRIES, LTD.
2,232 patents
- Zeon
ZEON CORPORATION
926 patents
- Compagnie Generale De…
COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN
1,844 patents
- Arlanxeo Deutschland 85
Arlanxeo Deutschland GmbH
85 patents
- The Yokohama Rubber
The Yokohama Rubber Co., LTD.
1,405 patents
- The Goodyear Tire & R…
The Goodyear Tire & Rubber Company
1,309 patents
- Michelin Recherche Et… 729
MICHELIN RECHERCHE ET TECHNIQUE S.A.
729 patents
- Jsr 375
JSR CORPORATION
375 patents
- Lanxess Deutschland 163
LANXESS Deutschland GmbH
163 patents
- Asahi Kasei Chemicals 169
ASAHI KASEI CHEMICALS CORPORATION
169 patents
- Natural Fiber Welding 23
Natural Fiber Welding, Inc.
23 patents
What this shows Bridgestone is the most active filer in C08C, holding 150 of the 1,240 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 C08C |
|---|---|---|
| #1 | BRIDGESTONE CORPORATION | 1,895 |
| #2 | SUMITOMO RUBBER INDUSTRIES, LTD. | 2,232 |
| #3 | ZEON CORPORATION | 926 |
| #4 | COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN | 1,844 |
| #5 | Arlanxeo Deutschland GmbH | 85 |
| #6 | The Yokohama Rubber Co., LTD. | 1,405 |
| #7 | The Goodyear Tire & Rubber Company | 1,309 |
| #8 | MICHELIN RECHERCHE ET TECHNIQUE S.A. | 729 |
| #9 | JSR CORPORATION | 375 |
| #10 | LANXESS Deutschland GmbH | 163 |
| #11 | ASAHI KASEI CHEMICALS CORPORATION | 169 |
| #12 | Natural Fiber Welding, Inc. | 23 |
| #13 | Versalis S.P.A. | 114 |
| #14 | Fina Technology, Inc. | 160 |
| #15 | TRINSEO EUROPE GMBH | 68 |
| #16 | Continental Reifen Deutschland GmbH | 325 |
| #17 | TOYO TIRE & RUBBER CO., LTD. | 339 |
| #18 | ENEOS MATERIALS CORPORATION | 15 |
| #19 | KOREA KUMHO PETROCHEMICAL CO., LTD. | 62 |
| #20 | MOLECULAR REBAR DESIGN, LLC | 36 |
About This Class
CPC subclass C08C belongs to class C08.
1,240 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 C08C?
How many patents have been filed in C08C?
Which company holds the most patents in C08C?
How is patent data for C08C collected?
What is the difference between CPC class and subclass?
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Read our methodology — how this data is sourced, computed, and verified.