CPC technology class · B41

B41K — Stamps

Stamps; stamping or numbering apparatus or devices. 197 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

197
US patents granted
B41
Parent CPC class
20
Active assignees
+3%
5-yr velocity
Top assignee: Trodat GmbH (21 patents)

CPC subclass B41K — STAMPS; STAMPING OR NUMBERING APPARATUS OR DEVICES — covers 197 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class B41 (PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS), 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 B41K 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 B41K is shaped by 20 distinct companies actively filing in this space. Trodat GmbH leads with 21 patents, followed by COLOP STEMPELERZEUGUNG SKOPEK GESELLSHAFT M.B.H. & CO. KG at 17 grants and Shachihata Inc. at 25. 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 B41K 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 B41K innovation accelerating?

US utility-patent grants per year in B41K, 2015–2025 — recent five years are up 3% versus 2015–2019.

51015202530 20152016201720182019202020212022202320242025 10

Who leads B41K?

The 12 most active assignees in STAMPS; STAMPING OR NUMBERING APPARATUS OR DEVICES — wider bars mean more grants

patents

What this shows Trodat is the most active filer in B41K, holding 21 of the 197 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 B41K belongs to class B41.

197 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 B41K?
CPC subclass B41K covers STAMPS; STAMPING OR NUMBERING APPARATUS OR DEVICES. It belongs to CPC class B41 (PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS). 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 B41K?
197 US utility patents were granted in CPC subclass B41K between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in B41K?
Trodat GmbH leads B41K with 21 patents, making it the most active assignee in this technology area.
How is patent data for B41K 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., B41) is a broad technology category. Subclasses like B41K 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