CPC technology class · C01

C01D — Compounds OF Alkali Metals

Compounds of alkali metals, i.e. lithium, sodium, potassium, rubidium, caesium, or francium. 976 US utility patents granted 2015–2025, with the leading assignees and year-by-year filing trajectory.

976
US patents granted
C01
Parent CPC class
20
Active assignees
+38%
5-yr velocity
Top assignee: NEMASKA LITHIUM INC. (22 patents)

CPC subclass C01D — COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM — covers 976 US utility patents granted between 2015 and 2025 according to USPTO PatentsView records. This subclass sits within the broader CPC class C01 (INORGANIC CHEMISTRY), 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 C01D 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 C01D is shaped by 20 distinct companies actively filing in this space. NEMASKA LITHIUM INC. leads with 22 patents, followed by NEMASKA LITHIUM INC. at 25 grants and Mangrove Water Technologies LTD. at 15. 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 C01D 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 C01D innovation accelerating?

US utility-patent grants per year in C01D, 2015–2025 — recent five years are up 38% versus 2015–2019.

60708090100 20152016201720182019202020212022202320242025 84

Who leads C01D?

The 12 most active assignees in COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM — wider bars mean more grants

patents

What this shows Nemaska Lithium is the most active filer in C01D, holding 22 of the 976 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 C01D belongs to class C01.

976 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 C01D?
CPC subclass C01D covers COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM. It belongs to CPC class C01 (INORGANIC CHEMISTRY). 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 C01D?
976 US utility patents were granted in CPC subclass C01D between 2015 and 2025, based on USPTO PatentsView data.
Which company holds the most patents in C01D?
NEMASKA LITHIUM INC. leads C01D with 22 patents, making it the most active assignee in this technology area.
How is patent data for C01D 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., C01) is a broad technology category. Subclasses like C01D 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