PlainPatent

CPC technology class · F01

F01B - Machines OR Engines

Machines or engines, in general or of positive-displacement type, e.g. steam engines. 754 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

754
US patents granted
F01
Parent CPC class
20
Active assignees
-16%
5-yr velocity

The verdict

Machines OR Engines ranks #486 of 670 CPC technology areas - 754 US patents granted since 2015, with filing down 16% over five years.

#486
of 670 CPC technology areas
754
US patents granted, 2015–2025
Achates Power
leading assignee (73)
-16%
filing velocity, last 5 yrs
Top assignee: Achates Power, Inc. (73 patents)

CPC subclass F01B - MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES - covers 754 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records, within the broader CPC class F01 (MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES). See our CPC classification guide for how the system works.

The competitive landscape in F01B is shaped by 20 distinct companies actively filing in this space. Achates Power, Inc. leads with 73 patents, followed by Aquarius Engines (a.m.) Ltd. at 16 grants and Hydro-gear Limited Partnership at 13.

Filing activity in F01B is down 16% over the past five years versus 2015-2019, a relatively steady filing pace. All counts come directly from USPTO PatentsView and reflect US granted utility patents only.

Is F01B innovation accelerating?

US utility-patent grants per year in F01B, 2015–2025 - recent five years are down 16% versus 2015–2019.

020406080100 20152016201720182019202020212022202320242025 23

Who leads F01B?

The 12 most active assignees in MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES - wider bars mean more grants

patents

What this shows Achates Power is the most active filer in F01B, holding 73 of the 754 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 F01B
Rank Company Patents in F01B
#1 Achates Power, Inc. 73
#2 Aquarius Engines (a.m.) Ltd. 16
#3 Hydro-gear Limited Partnership 13
#4 Mainspring Energy, Inc. 12
#5 Artemis Intelligent Power Limited 9
#6 Etagen, Inc. 9
#7 Getas Gesellschaft Für Thermodynamische Antriebssysteme Mbh 8
#8 HTS Llc 7
#9 Newlenoir Limited 7
#10 Kerr Machine Co. 6
#11 DANA Motion Systems Italia S.r.l. 6
#12 Linde Hydraulics Gmbh & Co. KG 6
#13 Obrist Technologies Gmbh 6
#14 CW Holdings Ltd 6
#15 Thermal Power Recovery Llc 6
#16 Enfield Engine Company, Inc. 6
#17 AVL Powertrain Engineering, Inc. 5
#18 Enginuity Power Systems, Inc. 5
#19 FNA Group, Inc. 4
#20 Danfoss Power Solutions Gmbh & Co. OHG 4

About This Class

CPC subclass F01B belongs to class F01.

754 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 F01B 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 F01B assignees by class footprint. Bubble size = patents in F01B. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Top 14 F01B assignees by class footprint. Bubble size = patents in F01B. Source: USPTO PatentsView (claim depth is company-wide across all classes). Scatter plot of 14 data points (bubble-sized by third dimension). 1015202530 020406080 Patents in F01B Avg claims / patent (company-wide) Achates PowerAquarius Engines (A M…Hydro-gear PartnershipMainspring EnergyArtemis Intelligent P…EtagenGetas Gesellschaft fü…HtsNewlenoirKerr MachineDana Motion Systems I…Linde Hydraulics & KgObristCw Holdings
Top 14 F01B assignees by class footprint. Bubble size = patents in F01B. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Frequently Asked Questions

What is CPC class F01B?
CPC subclass F01B covers MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES. It belongs to CPC class F01 (MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES), with 754 US utility patents granted since 2015.
How many patents have been filed in F01B?
754 US utility patents were granted in CPC subclass F01B between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in F01B?
Achates Power, Inc. leads F01B with 73 patents, making it the most active assignee in this technology area.
How is patent data for F01B 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., F01) is a broad technology category. Subclasses like F01B 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.