CPC technology class · F21

F21L — Lighting Devices OR Systems Thereof

Lighting devices or systems thereof, being portable or specially adapted for transportation. 1,327 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

1,327
US patents granted
F21
Parent CPC class
20
Active assignees
+17%
5-yr velocity
Top assignee: Milwaukee Electric Tool Corporation (94 patents)

CPC subclass F21L — LIGHTING DEVICES OR SYSTEMS THEREOF, BEING PORTABLE OR SPECIALLY ADAPTED FOR TRANSPORTATION — covers 1,327 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class F21 (LIGHTING), one of roughly 250 top-level technology categories in the Cooperative Patent Classification system jointly maintained by the USPTO and the European Patent Office. At the subclass level, four-character codes like F21L give the most practical resolution for tracking a specific technology domain without losing sight of adjacent filings. Every grant here has been classified by a USPTO examiner based on the technical disclosure in the patent specification.

The competitive landscape in F21L is shaped by 20 distinct companies actively filing in this space. Milwaukee Electric Tool Corporation leads with 94 patents, followed by Streamlight, Inc. at 156 grants and MAG INSTRUMENT, INC at 58. Concentration at the top of the leaderboard indicates whether this technology area is dominated by a handful of incumbents or fragmented across many filers — a useful signal for investors evaluating competitive moats and for product teams mapping freedom-to-operate risk.

Filing trajectory matters as much as static counts. The yearly series on this page plots grants from 2015 through 2025, highlighting whether innovation in F21L is accelerating, plateauing, or cooling. Technology areas with rising post-2020 activity often reflect emerging markets or new platform shifts, while declining filings can signal mature domains where incremental improvement has slowed. Researchers, licensing professionals, and competitive-intelligence teams use these patterns — together with the top-assignee distribution — to decide where to invest, where to license, and where to avoid entanglement. All counts on this page come directly from USPTO PatentsView and reflect US granted utility patents only.

Is F21L innovation accelerating?

US utility-patent grants per year in F21L, 2015–2025 — recent five years are up 17% versus 2015–2019.

80100120140160 20152016201720182019202020212022202320242025 88

Who leads F21L?

The 12 most active assignees in LIGHTING DEVICES OR SYSTEMS THEREOF, BEING PORTABLE OR SPECIALLY ADAPTED FOR TRANSPORTATION — wider bars mean more grants

patents

What this shows Milwaukee Electric To… is the most active filer in F21L, holding 94 of the 1,327 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

About This Class

CPC subclass F21L belongs to class F21.

1,327 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.

Frequently Asked Questions

What is CPC class F21L?
CPC subclass F21L covers LIGHTING DEVICES OR SYSTEMS THEREOF, BEING PORTABLE OR SPECIALLY ADAPTED FOR TRANSPORTATION. It belongs to CPC class F21 (LIGHTING). The Cooperative Patent Classification is a hierarchical system used by the USPTO and European Patent Office to categorize patents by technology.
How many patents have been filed in F21L?
1,327 US utility patents were granted in CPC subclass F21L between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in F21L?
Milwaukee Electric Tool Corporation leads F21L with 94 patents, making it the most active assignee in this technology area.
How is patent data for F21L 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., F21) is a broad technology category. Subclasses like F21L provide finer granularity within that category. PlainPatent organizes data at the subclass level (4-character codes) for the most useful view of technology domains.

Learn More

Explore the patent dataset

Data sourced from USPTO PatentsView — official U.S. government patent data. See our methodology for computation details. Retrieved and formatted by PlainPatent Editorial