PlainPatent

CPC technology class · C25

C25C - Processes For The Electrolytic Production

Processes for the electrolytic production, recovery or refining of metals; apparatus therefor. 753 US utility patents granted 2015–2025, with the leading assignees and year-by-year grant trajectory.

753
US patents granted
#3/4
in C25
6.4%
C25 class share
-8%
5-yr velocity

The verdict

According to USPTO PatentsView, Processes For The Electrolytic Production ranks #490 of 670 CPC technology areas - 753 US patents granted since 2015, with recorded grant volume down 8% over five years.

#490
of 670 CPC technology areas
753
US patents granted, 2015–2025
Freeport Minerals
leading assignee (23)
-8%
grant velocity, last 5 yrs

How C25C's grant cadence moved

Between 2020–2024, C25C recorded 321 grants versus 350 in 2015–2019 (-8% equal-window velocity). Across complete years, output peaked in 2019 at 83 grants and bottomed in 2023 at 50 (+66% peak-over-trough). Lead assignee Freeport Minerals Corporation holds 3.1% of the class ; the top three share 7.7%.

Leaderboard read

C25C concentration, lead at 3.1%

Freeport Minerals Corporation leads this historical grant record at 3.1% of C25C - foreign corporation assignees hold 64% of class grants (204 of 318). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share
3.1%

23 of 753 grants

Top three share
7.7%

of the class's recorded grants

Lead over #2
5

more grants than Industrie DE Nora S.P.A.

Where C25C sits inside C25

Among 4 subclasses in C25 (Electrolytic OR Electrophoretic PROCESSES; Apparatus Therefor), C25C ranks #3 and holds 6.4% 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 C25B 4,224 C25F 701

Rising assignees active in C25C

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. #1 Mangrove Water Technologies Ltd. 12x 0 → 12 company-wide · 10 in C25C
  2. #2 Jetti Resources, LLC 4.00x 0 → 4 company-wide · 5 in C25C
  3. #3 Obshchestvo S Ogranichennoy Otvetstvennost'yu “OBEDINENNAYA Kompaniya Rusal Inzhenerno-tekhnologicheskiy TSENTR” 4.00x 2 → 8 company-wide · 5 in C25C
  4. #4 Freeport Minerals Corporation 2.20x 10 → 22 company-wide · 23 in C25C
  5. #5 Norsk Hydro ASA 1.38x 8 → 11 company-wide · 6 in C25C

C25C grants by year, peak 2019 (83)

US utility-patent grants per year in C25C, 2015–2025 - recent five years are down 8% versus 2015–2019.

405060708090 20152016201720182019202020212022202320242025 43

Who leads C25C?

The 12 most active assignees in Processes FOR THE Electrolytic Production, Recovery OR Refining OF METALS; Apparatus Therefor - wider bars mean more grants

patents

What this shows Freeport Minerals is the most active filer in C25C, holding 23 of the 753 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 C25C
Rank Company Patents in C25C
#1 Freeport Minerals Corporation 23
#2 Industrie DE Nora S.P.A. 18
#3 United Company Rusal Engineering and Technology Centre LLC 17
#4 Rio Tinto Alcan International Limited 13
#5 Alcoa USA Corp. 13
#6 Outotec (FINLAND) OY 12
#7 Metalysis Limited 12
#8 Elysis Limited Partnership 11
#9 Pultrusion Technique Inc. 10
#10 Mangrove Water Technologies Ltd. 10
#11 Aqua Metals Inc. 10
#12 Shenzhen Sunxing Light Alloys Materials Co., Ltd. 8
#13 GE-Hitachi Nuclear Energy Americas LLC 7
#14 Consolidated Nuclear Security, LLC 7
#15 Alcoa Inc. 7
#16 Enlighten Innovations Inc. 7
#17 Norsk Hydro ASA 6
#18 Korea Institute Of Geoscience And Mineral Resources 5
#19 Outotec Oyj 5
#20 Obshchestvo S Ogranichennoy Otvetstvennost'yu “OBEDINENNAYA Kompaniya Rusal Inzhenerno-tekhnologicheskiy TSENTR” 5

Footprint here vs. claim strategy

Each dot is a leading C25C 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 C25C assignees by class footprint. Bubble size = patents in C25C. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 0510152025 510152025 Patents in C25C Avg claims / patent (company-wide) Freeport MineralsIndustrie De Nora S P…United Rusal…Rio Tinto Alcan…Alcoa UsaOutotec (Finland) OyMetalysisElysis PartnershipPultrusion TechniqueMangrove WaterAqua MetalsShenzhen Sunxing…Ge-hitachi Nuclear…Consolidated Nuclear…
Top 14 C25C assignees by class footprint. Bubble size = patents in C25C. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Classes near C25C's 753-grant footprint

Nationwide nearest neighbors for C25C (#490 of 670 by volume ; lead share 3.1%) - not the C25 parent-class siblings above.

Nearest by grant volume

C05C 753 C13K 754 F01B 754 F23K 754

Nearest by lead-assignee share

C25D 3.1% A01N 3.0% C04B 3.0% C08K 3.0%

Questions about C25C

Which company holds the most patents in C25C?
Freeport Minerals Corporation leads C25C with 23 patents (3.1% of the subclass). By PatentsView assignee type, foreign corporations account for 64% of class grants.
Which C25C assignees grew fastest recently?
Among assignees with ≥5 grants in C25C, Mangrove Water Technologies Ltd. shows the highest company-wide grant multiple (12x: 0 grants in 2019–2021 → 12 in 2022–2024) while holding 10 patents in this subclass. Growth is company-wide, not class-only.
How does C25C compare inside parent class C25?
Inside C25 (Electrolytic OR Electrophoretic PROCESSES; Apparatus Therefor), C25C ranks #3 of 4 subclasses by grant volume and holds 6.4% of the parent class total. The largest sibling is C25D (6,127 grants).

What to do with this data

C25C in context - here's where to go next.

  • Freeport Minerals Corporation leads C25C with 23 grants in this class. See full portfolio
  • C25C ranks #490 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 - C25C figures are USPTO PatentsView granted-utility totals for this subclass (753 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.