PlainPatent

CPC technology class · F23

F23B - Methods OR Apparatus FOR Combustion Using ONLY Solid FUEL

Methods or apparatus for combustion using only solid fuel. 220 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

220
US patents granted
F23
Parent CPC class
20
Active assignees
+51%
5-yr velocity

The verdict

Methods OR Apparatus FOR Combustion Using ONLY Solid FUEL ranks #596 of 670 CPC technology areas - 220 US patents granted since 2015, with filing up 51% over five years.

#596
of 670 CPC technology areas
220
US patents granted, 2015–2025
Weber-stephen Products
leading assignee (9)
+51%
filing velocity, last 5 yrs
Top assignee: Weber-stephen Products Llc (9 patents)

CPC subclass F23B - METHODS OR APPARATUS FOR COMBUSTION USING ONLY SOLID FUEL - covers 220 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 F23B is shaped by 20 distinct companies actively filing in this space. Weber-stephen Products Llc leads with 9 patents, followed by Clearsign Combustion Corporation at 9 grants and W.c. Bradley Co. at 5.

Filing activity in F23B is up 51% 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 F23B innovation accelerating?

US utility-patent grants per year in F23B, 2015–2025 - recent five years are up 51% versus 2015–2019.

1015202530 20152016201720182019202020212022202320242025 16

Who leads F23B?

The 12 most active assignees in METHODS OR APPARATUS FOR COMBUSTION USING ONLY SOLID FUEL - wider bars mean more grants

patents

What this shows Weber-stephen Products is the most active filer in F23B, holding 9 of the 220 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 F23B
Rank Company Patents in F23B
#1 Weber-stephen Products Llc 9
#2 Clearsign Combustion Corporation 9
#3 W.c. Bradley Co. 5
#4 Biochar Now, Llc 5
#5 Traeger Pellet Grills, Llc 4
#6 Biomass Controls, Llc 4
#7 Solo Brands, Llc 3
#8 Dansons US, Llc 3
#9 Maxitrol Company 3
#10 United States Stove Company 3
#11 Qingdao Genjoy Home Fashion Co., Ltd. 3
#12 Jupiter Oxygen Corporation 3
#13 North Atlantic Imports, Llc 2
#14 Royal Melbourne Institute OF Technology 2
#15 Alexza Pharmaceuticals, Inc. 2
#16 The Cashmere Caveman Co, Wild Kitchens Limited 2
#17 Sierra Space Corporation 2
#18 Biolite, Inc. 2
#19 Martin Gmbh Für Umwelt- Und Energietechik 2
#20 Onward Multi-corp. Inc. 2

About This Class

CPC subclass F23B belongs to class F23.

220 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 F23B 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 F23B assignees by class footprint. Bubble size = patents in F23B. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 F23B assignees by class footprint. Bubble size = patents in F23B. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 5101520253035 0246810 Patents in F23B Avg claims / patent (company-wide) Weber-stephen ProductsClearsign CombustionW C BradleyBiochar NowTraeger Pellet GrillsBiomass ControlsSolo BrandsDansons UsMaxitrolUnited States StoveQingdao Genjoy Home F…Jupiter OxygenNorth Atlantic ImportsRoyal Melbourne Insti…
Top 14 F23B assignees by class footprint. Bubble size = patents in F23B. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class F23B?
CPC subclass F23B covers METHODS OR APPARATUS FOR COMBUSTION USING ONLY SOLID FUEL. It belongs to CPC class F23 (COMBUSTION APPARATUS; COMBUSTION PROCESSES), with 220 US utility patents granted since 2015.
How many patents have been filed in F23B?
220 US utility patents were granted in CPC subclass F23B between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in F23B?
Weber-stephen Products Llc leads F23B with 9 patents, making it the most active assignee in this technology area.
How is patent data for F23B 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 F23B 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.