CPC technology class · G21

G21H - Obtaining Energy FROM Radioactive Sources

Obtaining energy from radioactive sources; applications of radiation from radioactive sources, not otherwise provided for; utilising cosmic radiation. 179 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

Compiled byPlainPatent Editorial, US Patent Intelligence Editorial Team · May 15, 2026

179
US patents granted: G21
Parent CPC class: 18
Active assignees: +38%
5-yr velocity

The verdict

Obtaining Energy FROM Radioactive Sources ranks #606 of 670 CPC technology areas - 179 US patents granted since 2015, with filing up 38% over five years.

#606
of 670 CPC technology areas: 179
US patents granted, 2015–2025: City Labs
leading assignee (14): +38%
filing velocity, last 5 yrs

Top assignee: CITY LABS, Inc. (14 patents)

CPC subclass G21H - OBTAINING ENERGY FROM RADIOACTIVE SOURCES; APPLICATIONS OF RADIATION FROM RADIOACTIVE SOURCES, NOT OTHERWISE PROVIDED FOR; UTILISING COSMIC RADIATION - covers 179 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class G21 (NUCLEAR PHYSICS; NUCLEAR ENGINEERING). See our CPC classification guide for how the system works.

The competitive landscape in G21H is shaped by 18 distinct companies actively filing in this space. CITY LABS, Inc. leads with 14 patents, followed by Westinghouse Electric Company Llc at 7 grants and Mb-microtec Ag at 5.

Filing activity in G21H is up 38% over the past five years versus 2015-2019, a sharp acceleration suggesting an emerging or fast-moving technology area. All counts come directly from USPTO PatentsView and reflect US granted utility patents only.

Is G21H innovation accelerating?

US utility-patent grants per year in G21H, 2015–2025 - recent five years are up 38% versus 2015–2019.

City Labs

14
Westinghouse Electric

7
mb-microtec

5
Bracco Diagnostics

4
Randaemon sp z o o

4
Howe Industries

4
The University of Bri…

3
Deep Isolation

3
Spark Thermionics

3
Holtec International

2
The University of Sus…

2
Faraday Defense

2

What this shows City Labs is the most active filer in G21H, holding 14 of the 179 patents in this class. Concentration at the top signals how contestable this technology area is for new entrants.

View data table

Top patent holders in CPC subclass G21H
Rank	Company	Patents in G21H
#1	CITY LABS, Inc.	14
#2	Westinghouse Electric Company Llc	7
#3	Mb-microtec Ag	5
#4	Bracco Diagnostics Inc.	4
#5	Randaemon Sp. Z O.o	4
#6	HOWE Industries Llc	4
#7	The University Of Bristol	3
#8	Deep Isolation, Inc.	3
#9	Spark Thermionics, Inc.	3
#10	Holtec International	2
#11	The University Of Sussex	2
#12	Faraday Defense Corporation	2
#13	ITM Isotopen Technologien München Ag	2
#14	Galvani Bioelectronics Limited	1
#15	AAI Corporation	1
#16	Atomic Energy OF Canada Limited/ènergie Atomique DU Canada Limitèe	1
#17	QSA Global Inc.	1
#18	Cammenga Company, Llc	1

About This Class

CPC subclass G21H belongs to class G21.

179 patents were granted in this class between 2015 and 2025.

18 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 G21H 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 G21H assignees by class footprint. Bubble size = patents in G21H. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class G21H?

CPC subclass G21H covers OBTAINING ENERGY FROM RADIOACTIVE SOURCES; APPLICATIONS OF RADIATION FROM RADIOACTIVE SOURCES, NOT OTHERWISE PROVIDED FOR; UTILISING COSMIC RADIATION. It belongs to CPC class G21 (NUCLEAR PHYSICS; NUCLEAR ENGINEERING), with 179 US utility patents granted since 2015.

How many patents have been filed in G21H?

179 US utility patents were granted in CPC subclass G21H between 2015 and 2025, based on USPTO PatentsView data.

Which company holds the most patents in G21H?

CITY LABS, Inc. leads G21H with 14 patents, making it the most active assignee in this technology area.

How is patent data for G21H 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., G21) is a broad technology category. Subclasses like G21H 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.