CPC technology class · G21

G21F - Protection Against X-radiation

Protection against x-radiation, gamma radiation, corpuscular radiation or particle bombardment; treating radioactively contaminated material; decontamination arrangements therefor. 1,599 US utility patents granted 2015–2025, with the leading assignees and year-by-year grant trajectory.

Compiled by PlainPatent · May 15, 2026

1,599
US patents granted: #3/8
in G21: 17.8%
G21 class share: -6%
5-yr velocity

The verdict

According to USPTO PatentsView, Protection Against X-radiation ranks #399 of 670 CPC technology areas - 1,599 US patents granted since 2015, with recorded grant volume down 6% over five years.

#399
of 670 CPC technology areas: 1,599
US patents granted, 2015–2025: Holtec International
leading assignee (111): -6%
grant velocity, last 5 yrs

How G21F's grant cadence moved

Between 2020–2024, G21F recorded 681 grants versus 723 in 2015–2019 (-6% equal-window velocity). Across complete years, output peaked in 2020 at 167 grants and bottomed in 2024 at 113 (+48% peak-over-trough). Lead assignee Holtec International holds 6.9% of the class ; the top three share 10.9%.

Leaderboard read

G21F concentration, lead at 6.9%

Holtec International leads this historical grant record at 6.9% of G21F - us corporation assignees hold 57% of class grants (508 of 892). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share: 6.9%
Top three share: 10.9%
Lead over #2: 78

Where G21F sits inside G21

Among 8 subclasses in G21 (Nuclear PHYSICS; Nuclear Engineering), G21F ranks #3 and holds 17.8% 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 G21D 744 G21G 629 G21B 372 G21H 179 G21J 5

Rising assignees active in G21F

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 Joint Stock Company “ROSENERGOATOM” 7.00x 1 → 7 company-wide · 5 in G21F
#2 NAC International Inc. 3.50x 2 → 7 company-wide · 12 in G21F
#3 Jubilant Draximage Inc. 3.00x 4 → 12 company-wide · 6 in G21F
#4 Rad Technology Medical Systems LLC 3.00x 1 → 3 company-wide · 6 in G21F
#5 Egg Medical, Inc. 2.33x 3 → 7 company-wide · 7 in G21F

G21F grants by year, peak 2020 (167)

US utility-patent grants per year in G21F, 2015–2025 - recent five years are down 6% versus 2015–2019.

Holtec International

111
Westinghouse Electric

33
Korea Atomic Energy…

30
Xyleco

30
Korea Hydro & Nuclear…

28
Deep Isolation

25
Tn International

21
Ge-hitachi Nuclear…

18
Framatome

17
Hitachi-ge Nuclear…

16
Bracco Diagnostics

16
Savannah River…

15

What this shows Holtec International is the most active filer in G21F, holding 111 of the 1,599 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 G21F
Rank	Company	Patents in G21F
#1	Holtec International	111
#2	Westinghouse Electric Company LLC	33
#3	Korea Atomic Energy Research Institute	30
#4	Xyleco, Inc.	30
#5	Korea Hydro & Nuclear Power Co., Ltd.	28
#6	Deep Isolation, Inc.	25
#7	TN International	21
#8	GE-Hitachi Nuclear Energy Americas LLC	18
#9	Framatome	17
#10	Hitachi-ge Nuclear Energy, Ltd.	16
#11	Bracco Diagnostics Inc.	16
#12	Savannah River Nuclear Solutions, LLC	15
#13	Areva GMBH	13
#14	Radux Devices, LLC	12
#15	NAC International Inc.	12
#16	Areva NC	11
#17	Kurion, Inc.	10
#18	Getinge LA Calhene	10
#19	EnergySolutions, Inc.	10
#20	Curium US LLC	9

Footprint here vs. claim strategy

Each dot is a leading G21F 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 G21F assignees by class footprint. Bubble size = patents in G21F. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Classes near G21F's 1,599-grant footprint

Nationwide nearest neighbors for G21F (#399 of 670 by volume ; lead share 6.9%) - not the G21 parent-class siblings above.

Nearest by grant volume

A23C 1,603 F41B 1,581 B26F 1,627 F23C 1,571

Nearest by lead-assignee share

Y02D 6.9% C09C 6.8% B23C 6.8% F21L 7.1%

Questions about G21F

Which company holds the most patents in G21F?

Holtec International leads G21F with 111 patents (6.9% of the subclass). By PatentsView assignee type, us corporations account for 57% of class grants.

Which G21F assignees grew fastest recently?

Among assignees with ≥5 grants in G21F, Joint Stock Company “ROSENERGOATOM” shows the highest company-wide grant multiple (7.00x: 1 grants in 2019–2021 → 7 in 2022–2024) while holding 5 patents in this subclass. Growth is company-wide, not class-only.

How does G21F compare inside parent class G21?

Inside G21 (Nuclear PHYSICS; Nuclear Engineering), G21F ranks #3 of 8 subclasses by grant volume and holds 17.8% of the parent class total. The largest sibling is G21K (3,019 grants).

What to do with this data

G21F in context - here's where to go next.

Holtec International leads G21F with 111 grants in this class. See full portfolio
G21F ranks #399 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 - G21F figures are USPTO PatentsView granted-utility totals for this subclass (1,599 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.