CPC technology class · F03

F03B - Machines Or Engines For Liquids

Machines or engines for liquids. 1,544 US utility patents granted 2015–2025, with the leading assignees and year-by-year grant trajectory.

Compiled by PlainPatent · May 15, 2026

1,544
US patents granted: #3/5
in F03: 13.0%
F03 class share: -2%
5-yr velocity

The verdict

According to USPTO PatentsView, Machines Or Engines For Liquids ranks #402 of 670 CPC technology areas - 1,544 US patents granted since 2015, with recorded grant volume down 2% over five years.

#402
of 670 CPC technology areas: 1,544
US patents granted, 2015–2025: Lone Gull Holdings
leading assignee (49): -2%
grant velocity, last 5 yrs

How F03B's grant cadence moved

Between 2020–2024, F03B recorded 666 grants versus 683 in 2015–2019 (-2% equal-window velocity). Across complete years, output peaked in 2017 at 163 grants and bottomed in 2015 at 111 (+47% peak-over-trough). Lead assignee Lone Gull Holdings, Ltd. holds 3.2% of the class ; the top three share 6.3%.

Leaderboard read

F03B concentration, lead at 3.2%

Lone Gull Holdings, Ltd. leads this historical grant record at 3.2% of F03B - us corporation assignees hold 54% of class grants (293 of 546). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share: 3.2%
Top three share: 6.3%
Lead over #2: 21

Where F03B sits inside F03

Among 5 subclasses in F03 (Machines OR Engines FOR LIQUIDS; Wind, Spring, OR Weight MOTORS; Producing Mechanical Power OR A Reactive Propulsive Thrust, NOT Otherwise Provided FOR), F03B ranks #3 and holds 13.0% of the parent class's 11,891 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.

F03D 7,370 F03G 2,252 F03C 404 F03H 321

Rising assignees active in F03B

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 Flower Turbines, Inc. 9.00x 0 → 9 company-wide · 11 in F03B
#2 Lone Gull Holdings, Ltd. 3.60x 10 → 36 company-wide · 49 in F03B
#3 Hangzhou LHD Institute OF NEW Energy, LLC 3.00x 0 → 3 company-wide · 6 in F03B
#4 Columbia Power Technologies, Inc. 3.00x 0 → 3 company-wide · 5 in F03B
#5 Emrgy Inc. 3.00x 1 → 3 company-wide · 5 in F03B

F03B grants by year, peak 2017 (163)

US utility-patent grants per year in F03B, 2015–2025 - recent five years are down 2% versus 2015–2019.

Lone Gull Holdings

49
Ge Renewable

28
Voith Patent

20
Liquid Robotics

12
Differential Dynamics

12
Aw-energy Oy

12
Flower Turbines

11
Andritz Hydro

11
Alstom Renewable

10
Murtech

10
Openhydro Ip

9
Michigan Technological…

8

What this shows Lone Gull Holdings is the most active filer in F03B, holding 49 of the 1,544 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 F03B
Rank	Company	Patents in F03B
#1	Lone Gull Holdings, Ltd.	49
#2	GE Renewable Technologies	28
#3	Voith Patent GmbH	20
#4	Liquid Robotics, Inc.	12
#5	Differential Dynamics Corporation	12
#6	Aw-energy OY	12
#7	Flower Turbines, Inc.	11
#8	Andritz Hydro GMBH	11
#9	Alstom Renewable Technologies	10
#10	Murtech, Inc.	10
#11	Openhydro IP Limited	9
#12	Michigan Technological University	8
#13	Natel Energy Holdings, Inc.	8
#14	Pliant Energy Systems Inc.	8
#15	Verno Holdings, LLC	8
#16	Ingine, Inc.	8
#17	Innovator Energy LLC.	7
#18	Oscilla Power Inc.	7
#19	Hydrokinetic Energy Corp	7
#20	Minesto AB	7

Footprint here vs. claim strategy

Each dot is a leading F03B 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 F03B assignees by class footprint. Bubble size = patents in F03B. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Classes near F03B's 1,544-grant footprint

Nationwide nearest neighbors for F03B (#402 of 670 by volume ; lead share 3.2%) - not the F03 parent-class siblings above.

Nearest by grant volume

C10B 1,527 F23C 1,571 E03D 1,515 F41B 1,581

Nearest by lead-assignee share

G06V 3.2% G01S 3.2% F16N 3.2% C30B 3.2%

Questions about F03B

Which company holds the most patents in F03B?

Lone Gull Holdings, Ltd. leads F03B with 49 patents (3.2% of the subclass). By PatentsView assignee type, us corporations account for 54% of class grants.

Which F03B assignees grew fastest recently?

Among assignees with ≥5 grants in F03B, Flower Turbines, Inc. shows the highest company-wide grant multiple (9.00x: 0 grants in 2019–2021 → 9 in 2022–2024) while holding 11 patents in this subclass. Growth is company-wide, not class-only.

How does F03B compare inside parent class F03?

Inside F03 (Machines OR Engines FOR LIQUIDS; Wind, Spring, OR Weight MOTORS; Producing Mechanical Power OR A Reactive Propulsive Thrust, NOT Otherwise Provided FOR), F03B ranks #3 of 5 subclasses by grant volume and holds 13.0% of the parent class total. The largest sibling is F03D (7,370 grants).

What to do with this data

F03B in context - here's where to go next.

Lone Gull Holdings, Ltd. leads F03B with 49 grants in this class. See full portfolio
F03B ranks #402 of 670 by grant volume among all tracked CPC technology areas. See the ranking
Inside parent class F03, the largest sibling subclass is F03D with 7,370 grants. Explore F03D

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

Methodology - F03B figures are USPTO PatentsView granted-utility totals for this subclass (1,544 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.