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 grant trajectory.

Compiled by PlainPatent · May 15, 2026

179
US patents granted: #7/8
in G21: 2.0%
G21 class share: +22%
5-yr velocity

The verdict

According to USPTO PatentsView, Obtaining Energy From Radioactive Sources ranks #606 of 670 CPC technology areas - 179 US patents granted since 2015, with recorded grant volume up 22% over five years.

#606
of 670 CPC technology areas: 179
US patents granted, 2015–2025: City Labs
leading assignee (14): +22%
grant velocity, last 5 yrs

How G21H's grant cadence moved

Between 2020–2024, G21H recorded 89 grants versus 73 in 2015–2019 (+22% equal-window velocity). Across complete years, output peaked in 2024 at 23 grants and bottomed in 2021 at 10 (+130% peak-over-trough). Lead assignee City Labs, Inc. holds 7.8% of the class ; the top three share 14.5%.

Leaderboard read

G21H concentration, lead at 7.8%

City Labs, Inc. leads this historical grant record at 7.8% of G21H - us corporation assignees hold 70% of class grants (42 of 60). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share: 7.8%
Top three share: 14.5%
Lead over #2: 7

Where G21H sits inside G21

Among 8 subclasses in G21 (Nuclear PHYSICS; Nuclear Engineering), G21H ranks #7 and holds 2.0% of the parent class's 8,981 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.

G21K 3,019 G21C 2,434 G21F 1,599 G21D 744 G21G 629 G21B 372 G21J 5

Rising assignees active in G21H

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 mb-microtec ag 5.00x 1 → 5 company-wide · 5 in G21H
#2 City Labs, Inc. 2.00x 3 → 6 company-wide · 14 in G21H
#3 Westinghouse Electric Company LLC 0.99x 103 → 102 company-wide · 7 in G21H

G21H grants by year, peak 2024 (23)

US utility-patent grants per year in G21H, 2015–2025 - recent five years are up 22% 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…

3
Deep Isolation

3
Spark Thermionics

3
Holtec International

2
The University of…

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

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).

Questions about G21H

Which company holds the most patents in G21H?

City Labs, Inc. leads G21H with 14 patents (7.8% of the subclass). By PatentsView assignee type, us corporations account for 70% of class grants.

Which G21H assignees grew fastest recently?

Among assignees with ≥5 grants in G21H, mb-microtec ag shows the highest company-wide grant multiple (5.00x: 1 grants in 2019–2021 → 5 in 2022–2024) while holding 5 patents in this subclass. Growth is company-wide, not class-only.

How does G21H compare inside parent class G21?

Inside G21 (Nuclear PHYSICS; Nuclear Engineering), G21H ranks #7 of 8 subclasses by grant volume and holds 2.0% of the parent class total. The largest sibling is G21K (3,019 grants).

What to do with this data

G21H in context - here's where to go next.

City Labs, Inc. leads G21H with 14 grants in this class. See full portfolio
G21H ranks #606 of 670 by grant volume among all tracked CPC technology areas. See the ranking
Inside parent class G21, the largest sibling subclass is G21K with 3,019 grants. Explore G21K

Figures reflect USPTO PatentsView grant data through 2026-05-15; pending applications not yet granted are not counted.

Methodology - G21H figures are USPTO PatentsView granted-utility totals for this subclass (179 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.