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 grant trajectory.

Compiled by PlainPatent · May 15, 2026

754
US patents granted: #8/8
in F01: 1.4%
F01 class share: -22%
5-yr velocity

The verdict

According to USPTO PatentsView, Machines Or Engines ranks #487 of 670 CPC technology areas - 754 US patents granted since 2015, with recorded grant volume down 22% over five years.

#487
of 670 CPC technology areas: 754
US patents granted, 2015–2025: Achates Power
leading assignee (73): -22%
grant velocity, last 5 yrs

How F01B's grant cadence moved

Between 2020–2024, F01B recorded 315 grants versus 402 in 2015–2019 (-22% equal-window velocity). Across complete years, output peaked in 2017 at 96 grants and bottomed in 2024 at 41 (+134% peak-over-trough). Lead assignee Achates Power, Inc. holds 9.7% of the class ; the top three share 13.5%.

Leaderboard read

F01B concentration, lead at 9.7%

Achates Power, Inc. leads this historical grant record at 9.7% of F01B - us corporation assignees hold 61% of class grants (195 of 322). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share: 9.7%
Top three share: 13.5%
Lead over #2: 57

Where F01B sits inside F01

Among 8 subclasses in F01 (Machines OR Engines IN GENERAL; Engine Plants IN GENERAL; Steam Engines), F01B ranks #8 and holds 1.4% of the parent class's 53,585 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.

F01D 24,492 F01N 12,144 F01L 4,152 F01P 4,129 F01M 3,398 F01K 2,854 F01C 1,662

Rising assignees active in F01B

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 Dana Motion Systems Italia S.R.L. 9.50x 4 → 38 company-wide · 6 in F01B
#2 Kerr Machine Co. 2.43x 21 → 51 company-wide · 6 in F01B
#3 Mainspring Energy, Inc. 2.00x 13 → 26 company-wide · 12 in F01B
#4 CW Holdings Ltd 1.40x 5 → 7 company-wide · 6 in F01B
#5 Aquarius Engines (A.M.) Ltd. 0.83x 6 → 5 company-wide · 16 in F01B

F01B grants by year, peak 2017 (96)

US utility-patent grants per year in F01B, 2015–2025 - recent five years are down 22% versus 2015–2019.

Achates Power

73
Aquarius Engines (A M…

16
Hydro-gear Partnership

13
Mainspring Energy

12
Artemis Intelligent…

9
Etagen

9
Getas Gesellschaft…

8
Hts

7
Newlenoir

7
Kerr Machine

6
Dana Motion Systems…

6
Linde Hydraulics & Kg

6

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.

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

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).

Classes near F01B's 754-grant footprint

Nationwide nearest neighbors for F01B (#487 of 670 by volume ; lead share 9.7%) - not the F01 parent-class siblings above.

Nearest by grant volume

C13K 754 F23K 754 C05C 753 C25C 753

Nearest by lead-assignee share

B64B 9.6% D04H 9.7% H02N 9.7% F24C 9.6%

Questions about F01B

Which company holds the most patents in F01B?

Achates Power, Inc. leads F01B with 73 patents (9.7% of the subclass). By PatentsView assignee type, us corporations account for 61% of class grants.

Which F01B assignees grew fastest recently?

Among assignees with ≥5 grants in F01B, Dana Motion Systems Italia S.R.L. shows the highest company-wide grant multiple (9.50x: 4 grants in 2019–2021 → 38 in 2022–2024) while holding 6 patents in this subclass. Growth is company-wide, not class-only.

How does F01B compare inside parent class F01?

Inside F01 (Machines OR Engines IN GENERAL; Engine Plants IN GENERAL; Steam Engines), F01B ranks #8 of 8 subclasses by grant volume and holds 1.4% of the parent class total. The largest sibling is F01D (24,492 grants).

What to do with this data

F01B in context - here's where to go next.

Achates Power, Inc. leads F01B with 73 grants in this class. See full portfolio
F01B ranks #487 of 670 by grant volume among all tracked CPC technology areas. See the ranking
Inside parent class F01, the largest sibling subclass is F01D with 24,492 grants. Explore F01D

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

Methodology - F01B figures are USPTO PatentsView granted-utility totals for this subclass (754 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.