CPC technology class · B28
B28B — Shaping CLAY OR Other Ceramic Compositions
Shaping clay or other ceramic compositions; shaping slag; shaping mixtures containing cementitious material, e.g. plaster. 3,309 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.
- 3,309
- US patents granted
- B28
- Parent CPC class
- 20
- Active assignees
- +71%
- 5-yr velocity
CPC subclass B28B — SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER — covers 3,309 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class B28 (WORKING CEMENT, CLAY, OR STONE), 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 B28B 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 B28B is shaped by 20 distinct companies actively filing in this space. CORNING INCORPORATED leads with 157 patents, followed by NGK INSULATORS, LTD. at 1,631 grants and UNITED STATES GYPSUM COMPANY 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 B28B 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 B28B innovation accelerating?
US utility-patent grants per year in B28B, 2015–2025 — recent five years are up 71% versus 2015–2019.
Who leads B28B?
The 12 most active assignees in SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER — wider bars mean more grants
- Corning Incorporated
CORNING INCORPORATED
3,494 patents
- Ngk Insulators
NGK INSULATORS, LTD.
1,631 patents
- United States Gypsum 233
UNITED STATES GYPSUM COMPANY
233 patents
- Concept Laser 166
Concept Laser, GmbH
166 patents
- Seurat 54
Seurat Technologies, Inc.
54 patents
- Velo3d 40
VELO3D, INC.
40 patents
- Arcam Ab 109
Arcam AB
109 patents
- Cambria 274
Cambria Company LLC
274 patents
- Desktop Metal 115
Desktop Metal, Inc.
115 patents
- Voxeljet 80
VOXELJET AG
80 patents
- Certainteed Gypsum 52
CertainTeed Gypsum, Inc.
52 patents
- Eos Electro Optical S… 112
EOS GmbH Electro Optical Systems
112 patents
What this shows Corning Incorporated is the most active filer in B28B, holding 157 of the 3,309 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 B28B |
|---|---|---|
| #1 | CORNING INCORPORATED | 3,494 |
| #2 | NGK INSULATORS, LTD. | 1,631 |
| #3 | UNITED STATES GYPSUM COMPANY | 233 |
| #4 | Concept Laser, GmbH | 166 |
| #5 | Seurat Technologies, Inc. | 54 |
| #6 | VELO3D, INC. | 40 |
| #7 | Arcam AB | 109 |
| #8 | Cambria Company LLC | 274 |
| #9 | Desktop Metal, Inc. | 115 |
| #10 | VOXELJET AG | 80 |
| #11 | CertainTeed Gypsum, Inc. | 52 |
| #12 | EOS GmbH Electro Optical Systems | 112 |
| #13 | SOLIDIA TECHNOLOGIES, INC. | 41 |
| #14 | ICON Technology, Inc. | 21 |
| #15 | SAFRAN CERAMICS | 110 |
| #16 | Knauf Gips KG | 64 |
| #17 | IBIDEN CO., LTD. | 467 |
| #18 | Elematic Oyj | 15 |
| #19 | YOSHINO GYPSUM CO., LTD. | 51 |
| #20 | PAVESTONE, LLC | 40 |
About This Class
CPC subclass B28B belongs to class B28.
3,309 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 B28B?
How many patents have been filed in B28B?
Which company holds the most patents in B28B?
How is patent data for B28B 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.