CPC technology class · E21
E21C - Mining Or Quarrying
Mining or quarrying. 1,136 US utility patents granted 2015–2025, with the leading assignees and year-by-year grant trajectory.
- 1,136
- US patents granted
- #2/4
- in E21
- 2.7%
- E21 class share
- -8%
- 5-yr velocity
The verdict
According to USPTO PatentsView, Mining Or Quarrying ranks #438 of 670 CPC technology areas - 1,136 US patents granted since 2015, with recorded grant volume down 8% over five years.
- #438
- of 670 CPC technology areas
- 1,136
- US patents granted, 2015–2025
- Wirtgen
- leading assignee (94)
- -8%
- grant velocity, last 5 yrs
How E21C's grant cadence moved
Between 2020–2024, E21C recorded 483 grants versus 524 in 2015–2019 (-8% equal-window velocity). Across complete years, output peaked in 2019 at 146 grants and bottomed in 2022 at 76 (+92% peak-over-trough). Lead assignee Wirtgen GmbH holds 8.3% of the class ; the top three share 19.6%.
Leaderboard read
E21C concentration, lead at 8.3%
Wirtgen GmbH leads this historical grant record at 8.3% of E21C - foreign corporation assignees hold 50% of class grants (388 of 773). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.
- Leader's share
- 8.3%
- Top three share
- 19.6%
- Lead over #2
- 12
94 of 1,136 grants
of the class's recorded grants
more grants than Joy Global Underground Mining LLC
Where E21C sits inside E21
Among 4 subclasses in E21 (Earth OR Rock DRILLING; Mining), E21C ranks #2 and holds 2.7% of the parent class's 42,682 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.
Rising assignees active in E21C
Company-wide grant multiples (2022–2024 vs 2019–2021) among assignees with ≥5 patents in this subclass. Growth is company-wide; class patent counts are subclass-specific.
- #1 Lunar Helium-3 Mining, LLC 5.00x 0 → 5 company-wide · 6 in E21C
- #2 Trans Astronautica Corporation 4.00x 3 → 12 company-wide · 9 in E21C
- #3 China University of Mining and Technology-Beijing 2.91x 11 → 32 company-wide · 13 in E21C
- #4 Taiyuan University OF Technology 2.40x 30 → 72 company-wide · 7 in E21C
- #5 Shandong University OF Science AND Technology 1.93x 29 → 56 company-wide · 12 in E21C
E21C grants by year, peak 2019 (146)
US utility-patent grants per year in E21C, 2015–2025 - recent five years are down 8% versus 2015–2019.
Who leads E21C?
The 12 most active assignees in Mining OR Quarrying - wider bars mean more grants
- Wirtgen
Wirtgen GmbH
94 patents
- Joy Global Underground…
Joy Global Underground Mining LLC
82 patents
- Joy Mm Delaware
Joy MM Delaware, Inc.
47 patents
- The Sollami
The Sollami Company
46 patents
- China University of…
China University of Mining and Technology
42 patents
- Caterpillar Global… 26
Caterpillar Global Mining Europe GmbH
26 patents
- Sandvik Intellectual… 25
Sandvik Intellectual Property AB
25 patents
- Kennametal 23
Kennametal Inc.
23 patents
- Caterpillar Paving… 23
Caterpillar Paving Products Inc.
23 patents
- Joy Global Surface… 23
Joy Global Surface Mining Inc
23 patents
- Sandvik Mining and… 17
Sandvik Mining and Construction Oy
17 patents
- Us Synthetic 15
US Synthetic Corporation
15 patents
What this shows Wirtgen is the most active filer in E21C, holding 94 of the 1,136 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 E21C |
|---|---|---|
| #1 | Wirtgen GmbH | 94 |
| #2 | Joy Global Underground Mining LLC | 82 |
| #3 | Joy MM Delaware, Inc. | 47 |
| #4 | The Sollami Company | 46 |
| #5 | China University of Mining and Technology | 42 |
| #6 | Caterpillar Global Mining Europe GmbH | 26 |
| #7 | Sandvik Intellectual Property AB | 25 |
| #8 | Kennametal Inc. | 23 |
| #9 | Caterpillar Paving Products Inc. | 23 |
| #10 | Joy Global Surface Mining Inc | 23 |
| #11 | Sandvik Mining and Construction Oy | 17 |
| #12 | US Synthetic Corporation | 15 |
| #13 | Bomag GmbH | 15 |
| #14 | Harnischfeger Technologies, Inc. | 15 |
| #15 | China University of Mining and Technology-Beijing | 13 |
| #16 | Betek GmbH & Co. KG | 13 |
| #17 | Shandong University OF Science AND Technology | 12 |
| #18 | Element Six Limited | 12 |
| #19 | Vermeer Manufacturing Company | 11 |
| #20 | Element SIX Abrasives S.A. | 10 |
Footprint here vs. claim strategy
Each dot is a leading E21C assignee, placed by how many patents it holds in this class (horizontal) against its company-wide average claims per patent (vertical) - a read on whether the class is led by broad-but-shallow filers or focused deep-claim players.
Classes near E21C's 1,136-grant footprint
Nationwide nearest neighbors for E21C (#438 of 670 by volume ; lead share 8.3%) - not the E21 parent-class siblings above.
Nearest by grant volume
Questions about E21C
Which company holds the most patents in E21C?
Which E21C assignees grew fastest recently?
How does E21C compare inside parent class E21?
What to do with this data
E21C in context - here's where to go next.
- Wirtgen GmbH leads E21C with 94 grants in this class. See full portfolio
- E21C ranks #438 of 670 by grant volume among all tracked CPC technology areas. See the ranking
- Inside parent class E21, the largest sibling subclass is E21B with 39,943 grants. Explore E21B
Figures reflect USPTO PatentsView grant data through 2026-05-15; pending applications not yet granted are not counted.
Methodology - E21C figures are USPTO PatentsView granted-utility totals for this subclass (1,136 grants in the tracked window).
Every figure on PlainPatent is rendered directly from USPTO source data, no number is typed in by an editor. This page draws directly on USPTO source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.