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 grant trajectory.

Compiled by PlainPatent · May 15, 2026

4,224
US patents granted: #2/4
in C25: 35.8%
C25 class share: +33%
5-yr velocity

The verdict

According to USPTO PatentsView, Electrolytic Or Electrophoretic Processes For The Product… ranks #265 of 670 CPC technology areas - 4,224 US patents granted since 2015, with recorded grant volume up 33% over five years.

#265
of 670 CPC technology areas: 4,224
US patents granted, 2015–2025: Toshiba
leading assignee (76): +33%
grant velocity, last 5 yrs

How C25B's grant cadence moved

Between 2020–2024, C25B recorded 1,976 grants versus 1,483 in 2015–2019 (+33% equal-window velocity). Across complete years, output peaked in 2024 at 472 grants and bottomed in 2016 at 253 (+87% peak-over-trough). Lead assignee King Fahd University OF Petroleum AND Minerals holds 1.7% of the class ; the top three share 3.2%.

Leaderboard read

C25B concentration, lead at 1.7%

King Fahd University OF Petroleum AND Minerals leads this historical grant record at 1.7% of C25B - foreign corporation assignees hold 50% of class grants (784 of 1,571). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share: 1.7%
Top three share: 3.2%
Lead over #2: 38

Where C25B sits inside C25

Among 4 subclasses in C25 (Electrolytic OR Electrophoretic PROCESSES; Apparatus Therefor), C25B ranks #2 and holds 35.8% of the parent class's 11,805 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.

C25D 6,127 C25C 753 C25F 701

Rising assignees active in C25B

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 Totalenergies Onetech 65x 0 → 65 company-wide · 8 in C25B
#2 Rondo Energy, Inc. 36x 0 → 36 company-wide · 30 in C25B
#3 FFI Ionix IP, Inc. 23x 0 → 23 company-wide · 13 in C25B
#4 Utility Global, Inc. 17x 0 → 17 company-wide · 9 in C25B
#5 Topsoe A/S 17x 0 → 17 company-wide · 7 in C25B

C25B grants by year, peak 2024 (472)

US utility-patent grants per year in C25B, 2015–2025 - recent five years are up 33% 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

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).

Classes near C25B's 4,224-grant footprint

Nationwide nearest neighbors for C25B (#265 of 670 by volume ; lead share 1.8%) - not the C25 parent-class siblings above.

Nearest by grant volume

Y02C 4,229 B67D 4,233 C10M 4,240 B60B 4,268

Nearest by lead-assignee share

C12Q 1.8% B29B 1.8% E04B 1.8% C01B 1.8%

Questions about C25B

Which company holds the most patents in C25B?

Kabushiki Kaisha Toshiba leads C25B with 76 patents (1.7% of the subclass). By PatentsView assignee type, foreign corporations account for 50% of class grants.

Which C25B assignees grew fastest recently?

Among assignees with ≥5 grants in C25B, Totalenergies Onetech shows the highest company-wide grant multiple (65x: 0 grants in 2019–2021 → 65 in 2022–2024) while holding 8 patents in this subclass. Growth is company-wide, not class-only.

How does C25B compare inside parent class C25?

Inside C25 (Electrolytic OR Electrophoretic PROCESSES; Apparatus Therefor), C25B ranks #2 of 4 subclasses by grant volume and holds 35.8% of the parent class total. The largest sibling is C25D (6,127 grants).

What to do with this data

C25B in context - here's where to go next.

King Fahd University OF Petroleum AND Minerals leads C25B with 71 grants in this class. See full portfolio
C25B ranks #265 of 670 by grant volume among all tracked CPC technology areas. See the ranking
Inside parent class C25, the largest sibling subclass is C25D with 6,127 grants. Explore C25D

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

Methodology - C25B figures are USPTO PatentsView granted-utility totals for this subclass (4,224 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.