PlainPatent

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 filing trajectory.

1,136
US patents granted
E21
Parent CPC class
20
Active assignees
+3%
5-yr velocity

The verdict

Mining OR Quarrying ranks #438 of 670 CPC technology areas - 1,136 US patents granted since 2015, with filing up 3% over five years.

#438
of 670 CPC technology areas
1,136
US patents granted, 2015–2025
Wirtgen
leading assignee (94)
+3%
filing velocity, last 5 yrs
Top assignee: Wirtgen Gmbh (94 patents)

CPC subclass E21C - MINING OR QUARRYING - covers 1,136 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class E21 (EARTH OR ROCK DRILLING; MINING). See our CPC classification guide for how the system works.

The competitive landscape in E21C is shaped by 20 distinct companies actively filing in this space. Wirtgen Gmbh leads with 94 patents, followed by Joy Global Underground Mining Llc at 82 grants and Joy MM Delaware, Inc. at 47.

Filing activity in E21C is up 3% over the past five years versus 2015-2019, a relatively steady filing pace. All counts come directly from USPTO PatentsView and reflect US granted utility patents only.

Is E21C innovation accelerating?

US utility-patent grants per year in E21C, 2015–2025 - recent five years are up 3% versus 2015–2019.

406080100120140160 20152016201720182019202020212022202320242025 58

Who leads E21C?

The 12 most active assignees in MINING OR QUARRYING - wider bars mean more grants

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.

Source USPTO PatentsView, granted utility patents As of 2015–2025 grant years
View data table
Top patent holders in CPC subclass E21C
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

About This Class

CPC subclass E21C belongs to class E21.

1,136 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.

← All Technology Classes Technology Rankings →

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.

Top 14 E21C assignees by class footprint. Bubble size = patents in E21C. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 E21C assignees by class footprint. Bubble size = patents in E21C. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 510152025 020406080100 Patents in E21C Avg claims / patent (company-wide) WirtgenJoy Global Undergroun…Joy Mm DelawareThe SollamiChina University of M…Caterpillar Global Mi…Sandvik Intellectual…KennametalCaterpillar Paving Pr…Joy Global Surface Mi…Sandvik Mining and Co…Us SyntheticBomagHarnischfeger
Top 14 E21C assignees by class footprint. Bubble size = patents in E21C. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class E21C?
CPC subclass E21C covers MINING OR QUARRYING. It belongs to CPC class E21 (EARTH OR ROCK DRILLING; MINING), with 1,136 US utility patents granted since 2015.
How many patents have been filed in E21C?
1,136 US utility patents were granted in CPC subclass E21C between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in E21C?
Wirtgen Gmbh leads E21C with 94 patents, making it the most active assignee in this technology area.
How is patent data for E21C collected?
Patent data comes from USPTO PatentsView, a public research dataset maintained by the United States Patent and Trademark Office. It covers all US granted utility patents and assigns CPC codes based on the technology described in each patent.
What is the difference between CPC class and subclass?
A CPC class (e.g., E21) is a broad technology category. Subclasses like E21C provide finer granularity within that category. PlainPatent organizes data at the subclass level (4-character codes) for the most useful view of technology domains.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from USPTO PatentsView - official U.S. government patent data. See our methodology for computation details. Retrieved and formatted by PlainPatent Editorial

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.