CPC technology class · F21

F21Y - Indexing Scheme Associated With Subclasses F21k

Indexing scheme associated with subclasses f21k, f21l, f21s and f21v, relating to the form or the kind of the light sources or of the colour of the light emitted. 17,865 US utility patents granted 2015–2025, with the leading assignees and year-by-year grant trajectory.

Compiled by PlainPatent · May 15, 2026

17,865
US patents granted: #2/6
in F21: 24.8%
F21 class share: -5%
5-yr velocity

The verdict

According to USPTO PatentsView, Indexing Scheme Associated With Subclasses F21k ranks #106 of 670 CPC technology areas - 17,865 US patents granted since 2015, with recorded grant volume down 5% over five years.

#106
of 670 CPC technology areas: 17,865
US patents granted, 2015–2025: Signify Holding B V
leading assignee (557): -5%
grant velocity, last 5 yrs

How F21Y's grant cadence moved

Between 2020–2024, F21Y recorded 7,998 grants versus 8,452 in 2015–2019 (-5% equal-window velocity). Across complete years, output peaked in 2019 at 2,272 grants and bottomed in 2015 at 1,295 (+75% peak-over-trough). Lead assignee Signify Holding B.V. holds 3.1% of the class ; the top three share 6.9%.

Leaderboard read

F21Y concentration, lead at 3.1%

Signify Holding B.V. leads this historical grant record at 3.1% of F21Y - foreign corporation assignees hold 53% of class grants (6,565 of 12,276). Figures describe granted US utility patents in this CPC subclass, not current investment or legal strength.

Leader's share: 3.1%
Top three share: 6.9%
Lead over #2: 205

Where F21Y sits inside F21

Among 6 subclasses in F21 (Lighting), F21Y ranks #2 and holds 24.8% of the parent class's 72,153 recorded grants. Sibling chips below are the other subclasses in the same parent class, not the nationwide volume/lead-share peers further down.

F21V 23,679 F21S 15,705 F21K 7,021 F21W 6,556 F21L 1,327

Rising assignees active in F21Y

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 Korrus, Inc. 71x 0 → 71 company-wide · 35 in F21Y
#2 HLI Solutions, Inc. 46x 0 → 46 company-wide · 23 in F21Y
#3 Dongguan Huihuan Lighting Co., Ltd 35x 0 → 35 company-wide · 14 in F21Y
#4 Hubbell Lighting, Inc. 32x 0 → 32 company-wide · 18 in F21Y
#5 Xiamen Longstar Lighting Co., Ltd. 30x 0 → 30 company-wide · 10 in F21Y

F21Y grants by year, peak 2019 (2,272)

US utility-patent grants per year in F21Y, 2015–2025 - recent five years are down 5% versus 2015–2019.

Signify Holding B V

557
Cree

352
Lg Innotek

327
Nichia

282
Osram

247
Lumileds

225
Philips Lighting…

221
Jiaxing Super…

207
Abl Ip Holding

194
Xiamen Eco Lighting

193
Cooper

171
Koito Manufacturing

161

What this shows Signify Holding B V is the most active filer in F21Y, holding 557 of the 17,865 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 F21Y
Rank	Company	Patents in F21Y
#1	Signify Holding B.V.	557
#2	Cree, Inc.	352
#3	LG Innotek Co., Ltd.	327
#4	Nichia Corporation	282
#5	Osram GmbH	247
#6	Lumileds LLC	225
#7	Philips Lighting Holding B.V.	221
#8	Jiaxing Super Lighting Electric Appliance Co., Ltd	207
#9	ABL IP Holding LLC	194
#10	Xiamen ECO Lighting Co. Ltd.	193
#11	Cooper Technologies Company	171
#12	Koito Manufacturing Co., Ltd.	161
#13	Ledvance GMBH	157
#14	Hubbell Incorporated	152
#15	Valeo Vision	147
#16	Ideal Industries Lighting LLC	120
#17	Eaton Intelligent Power Limited	119
#18	Opple Lighting Co., Ltd.	113
#19	Feit Electric Company, Inc.	107
#20	Milwaukee Electric Tool Corporation	97

Footprint here vs. claim strategy

Each dot is a leading F21Y 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 F21Y assignees by class footprint. Bubble size = patents in F21Y. Source: USPTO PatentsView (claim depth is company-wide across all classes).

Classes near F21Y's 17,865-grant footprint

Nationwide nearest neighbors for F21Y (#106 of 670 by volume ; lead share 3.1%) - not the F21 parent-class siblings above.

Nearest by grant volume

F16K 17,624 A63F 18,220 B65G 17,344 C12Y 17,214

Nearest by lead-assignee share

G06T 3.1% B21K 3.1% E01D 3.1% F16B 3.1%

Questions about F21Y

Which company holds the most patents in F21Y?

Signify Holding B.V. leads F21Y with 557 patents (3.1% of the subclass). By PatentsView assignee type, foreign corporations account for 53% of class grants.

Which F21Y assignees grew fastest recently?

Among assignees with ≥5 grants in F21Y, Korrus, Inc. shows the highest company-wide grant multiple (71x: 0 grants in 2019–2021 → 71 in 2022–2024) while holding 35 patents in this subclass. Growth is company-wide, not class-only.

How does F21Y compare inside parent class F21?

Inside F21 (Lighting), F21Y ranks #2 of 6 subclasses by grant volume and holds 24.8% of the parent class total. The largest sibling is F21V (23,679 grants).

What to do with this data

F21Y in context - here's where to go next.

Signify Holding B.V. leads F21Y with 557 grants in this class. See full portfolio
F21Y ranks #106 of 670 by grant volume among all tracked CPC technology areas. See the ranking
Inside parent class F21, the largest sibling subclass is F21V with 23,679 grants. Explore F21V

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

Methodology - F21Y figures are USPTO PatentsView granted-utility totals for this subclass (17,865 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.