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CPC technology class · G21

G21G - Conversion OF Chemical Elements

Conversion of chemical elements; radioactive sources. 629 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

629
US patents granted
G21
Parent CPC class
20
Active assignees
+58%
5-yr velocity

The verdict

Conversion OF Chemical Elements ranks #515 of 670 CPC technology areas - 629 US patents granted since 2015, with filing up 58% over five years.

#515
of 670 CPC technology areas
629
US patents granted, 2015–2025
Curium Us
leading assignee (25)
+58%
filing velocity, last 5 yrs
Top assignee: Curium US Llc (25 patents)

CPC subclass G21G - CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES - covers 629 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 G21G is shaped by 20 distinct companies actively filing in this space. Curium US Llc leads with 25 patents, followed by Bracco Diagnostics Inc. at 19 grants and Westinghouse Electric Company Llc at 17.

Filing activity in G21G is up 58% 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 G21G innovation accelerating?

US utility-patent grants per year in G21G, 2015–2025 - recent five years are up 58% versus 2015–2019.

4050607080 20152016201720182019202020212022202320242025 54

Who leads G21G?

The 12 most active assignees in CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES - wider bars mean more grants

patents

What this shows Curium Us is the most active filer in G21G, holding 25 of the 629 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 G21G
Rank Company Patents in G21G
#1 Curium US Llc 25
#2 Bracco Diagnostics Inc. 19
#3 Westinghouse Electric Company Llc 17
#4 Neuboron Medtech Ltd. 17
#5 Ge-hitachi Nuclear Energy Americas Llc 15
#6 QSA Global Inc. 13
#7 Shine Technologies, Llc 11
#8 BWXT Isotope Technology Group, Inc. 10
#9 Framatome 9
#10 Jubilant Draximage Inc. 9
#11 GE Healthcare Limited 8
#12 Adelphi Technology, Inc. 8
#13 Mallinckrodt Nuclear Medicine Llc 7
#14 Texas Thorium Llc 7
#15 Ion Beam Applications 6
#16 Orano MED 6
#17 Neutron Therapeutics Llc 5
#18 Mallinckrodt Llc 4
#19 General Atomics 4
#20 Nihon Medi-physics Co., Ltd. 4

About This Class

CPC subclass G21G belongs to class G21.

629 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 G21G 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 G21G assignees by class footprint. Bubble size = patents in G21G. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 G21G assignees by class footprint. Bubble size = patents in G21G. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 510152025 51015202530 Patents in G21G Avg claims / patent (company-wide) Curium UsBracco DiagnosticsWestinghouse ElectricNeuboron MedtechGe-hitachi Nuclear En…Qsa GlobalShineBwxt Isotope Technolo…FramatomeJubilant DraximageGe HealthcareAdelphi TechnologyMallinckrodt Nuclear…Texas Thorium
Top 14 G21G assignees by class footprint. Bubble size = patents in G21G. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class G21G?
CPC subclass G21G covers CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES. It belongs to CPC class G21 (NUCLEAR PHYSICS; NUCLEAR ENGINEERING), with 629 US utility patents granted since 2015.
How many patents have been filed in G21G?
629 US utility patents were granted in CPC subclass G21G between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in G21G?
Curium US Llc leads G21G with 25 patents, making it the most active assignee in this technology area.
How is patent data for G21G 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 G21G 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.