PlainPatent

CPC technology class · F23

F23C - Methods OR Apparatus FOR Combustion Using Fluid FUEL OR S…

Methods or apparatus for combustion using fluid fuel or solid fuel suspended in  ; a carrier gas or; air. 1,571 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

1,571
US patents granted
F23
Parent CPC class
20
Active assignees
-29%
5-yr velocity

The verdict

Methods OR Apparatus FOR Combustion Using Fluid FUEL OR S… ranks #401 of 670 CPC technology areas - 1,571 US patents granted since 2015, with filing down 29% over five years.

#401
of 670 CPC technology areas
1,571
US patents granted, 2015–2025
General Electric
leading assignee (85)
-29%
filing velocity, last 5 yrs
Top assignee: General Electric Company (85 patents)

CPC subclass F23C - METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  ; A CARRIER GAS OR; AIR - covers 1,571 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class F23 (COMBUSTION APPARATUS; COMBUSTION PROCESSES). See our CPC classification guide for how the system works.

The competitive landscape in F23C is shaped by 20 distinct companies actively filing in this space. General Electric Company leads with 85 patents, followed by General Electric Technology Gmbh at 42 grants and Ansaldo Energia Switzerland Ag at 28.

Filing activity in F23C is down 29% over the past five years versus 2015-2019, a notable slowdown that may signal a maturing field. All counts come directly from USPTO PatentsView and reflect US granted utility patents only.

Is F23C innovation accelerating?

US utility-patent grants per year in F23C, 2015–2025 - recent five years are down 29% versus 2015–2019.

50100150200 20152016201720182019202020212022202320242025 74

Who leads F23C?

The 12 most active assignees in METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  ; A CARRIER GAS OR; AIR - wider bars mean more grants

patents

What this shows General Electric is the most active filer in F23C, holding 85 of the 1,571 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 F23C
Rank Company Patents in F23C
#1 Clearsign Combustion Corporation 65
#2 General Electric Technology Gmbh 42
#3 Ansaldo Energia Switzerland Ag 28
#4 Exxonmobil Upstream Research Company 24
#5 IFP Energies Nouvelles 21
#6 Alstom Technology Ltd 21
#7 Ener-core Power, Inc. 19
#8 AIR Products AND Chemicals, Inc. 17
#9 Clearsign Technologies Corporation 17
#10 8 Rivers Capital, Llc 15
#11 Delavan Inc. 14
#12 Eberspächer Climate Control Systems Gmbh 13
#13 The Babcock & Wilcox Company 10
#14 Total Raffinage Chimie 10
#15 Sumitomo SHI FW Energia Oy 10
#16 Total Sa 9
#17 GAS Technology Institute 9
#18 Linde Gmbh 8
#19 Noritz Corporation 8
#20 Valmet Technologies Oy 8

About This Class

CPC subclass F23C belongs to class F23.

1,571 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 F23C 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 F23C assignees by class footprint. Bubble size = patents in F23C. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 F23C assignees by class footprint. Bubble size = patents in F23C. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 10152025303540 020406080 Patents in F23C Avg claims / patent (company-wide) Clearsign CombustionGeneral Electric Tech…Ansaldo Energia Switz…Exxonmobil Upstream R…Ifp Energies NouvellesAlstom TechnologyEner-core PowerAir Products And Chem…Clearsign8 Rivers CapitalDelavanEberspÄCher Climate C…The Babcock & WilcoxTotal Raffinage Chimie
Top 14 F23C assignees by class footprint. Bubble size = patents in F23C. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class F23C?
CPC subclass F23C covers METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  ; A CARRIER GAS OR; AIR. It belongs to CPC class F23 (COMBUSTION APPARATUS; COMBUSTION PROCESSES), with 1,571 US utility patents granted since 2015.
How many patents have been filed in F23C?
1,571 US utility patents were granted in CPC subclass F23C between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in F23C?
General Electric Company leads F23C with 85 patents, making it the most active assignee in this technology area.
How is patent data for F23C 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., F23) is a broad technology category. Subclasses like F23C 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.