CPC technology class · C25

C25B - Electrolytic OR Electrophoretic Processes FOR THE Product…

Electrolytic or electrophoretic processes for the production of compounds or non-metals; apparatus therefor. 4,224 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

4,224
US patents granted: C25
Parent CPC class: 20
Active assignees: +63%
5-yr velocity

The verdict

Electrolytic OR Electrophoretic Processes FOR THE Product… ranks #265 of 670 CPC technology areas - 4,224 US patents granted since 2015, with filing up 63% over five years.

#265
of 670 CPC technology areas: 4,224
US patents granted, 2015–2025: Toshiba
leading assignee (76): +63%
filing velocity, last 5 yrs

Top assignee: Kabushiki Kaisha Toshiba (76 patents)

CPC subclass C25B - ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR - covers 4,224 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class C25 (ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR). See our CPC classification guide for how the system works.

The competitive landscape in C25B is shaped by 20 distinct companies actively filing in this space. Kabushiki Kaisha Toshiba leads with 76 patents, followed by Industrie DE NORA S.p.a. at 33 grants and C2cnt Llc at 32.

Filing activity in C25B is up 63% 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 C25B innovation accelerating?

US utility-patent grants per year in C25B, 2015–2025 - recent five years are up 63% versus 2015–2019.

King Fahd University…

71
Industrie De Nora S P…

33
C2cnt

32
De Nora Permelec

32
Rondo Energy

30
Nuvera Fuel Cells

28
Asahi Kasei

26
Dioxide Materials

24
Calera

23
Bloom Energy

21
Haldor TopsØE A/S

20
Colgate-palmolive

19

What this shows Toshiba is the most active filer in C25B, holding 76 of the 4,224 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 C25B
Rank	Company	Patents in C25B
#1	KING FAHD University OF Petroleum AND Minerals	71
#2	Industrie DE NORA S.p.a.	33
#3	C2cnt Llc	32
#4	DE NORA Permelec Ltd	32
#5	Rondo Energy, Inc.	30
#6	Nuvera Fuel Cells, Llc	28
#7	Asahi Kasei Kabushiki Kaisha	26
#8	Dioxide Materials, Inc.	24
#9	Calera Corporation	23
#10	Bloom Energy Corporation	21
#11	Haldor Topsøe A/s	20
#12	Colgate-palmolive Company	19
#13	Nemaska Lithium Inc.	18
#14	Infinium Technology, Llc	18
#15	Twelve Benefit Corporation	18
#16	Ohmium International, Inc.	17
#17	Evoqua Water Technologies Llc	16
#18	Japan Technological Research Association OF Artificial Photosynthetic Chemical Process	16
#19	Ceramatec, Inc.	15
#20	Avantium Knowledge Centre B.v.	14

About This Class

CPC subclass C25B belongs to class C25.

4,224 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 C25B 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 C25B assignees by class footprint. Bubble size = patents in C25B. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class C25B?

CPC subclass C25B covers ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR. It belongs to CPC class C25 (ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR), with 4,224 US utility patents granted since 2015.

How many patents have been filed in C25B?

4,224 US utility patents were granted in CPC subclass C25B between 2015 and 2025, based on USPTO PatentsView data.

Which company holds the most patents in C25B?

Kabushiki Kaisha Toshiba leads C25B with 76 patents, making it the most active assignee in this technology area.

How is patent data for C25B 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., C25) is a broad technology category. Subclasses like C25B 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.