PlainPatent
USPTO 2015–2025 USPTO PatentsView US Corporation

Clearsign Combustion Corporation

USPTO PatentsView assignee record - 81 granted patents across 42 technology areas, active 2015–2022. Filing-trend and competitive-moat analysis cross-referenced to USPTO Patent Public Search. Primary class: F23C (METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  ; A CARRIER GAS OR; AIR).

Explore the portfolio See the ranking
81
Total patents granted
42
CPC technology areas
30.3
Avg claims per patent
-95%
5-year filing velocity

The verdict

Clearsign holds 81 US patents across 42 technology areas, rank #4,371 of 50,000 tracked assignees.

#4,371
of 50,000 US assignees by volume
Top 9%
by Innovation Score (53.5/100)
30.3
avg claims per patent
-95%
filing velocity, last 5 yrs

Portfolio overview

Clearsign Combustion Corporation has been granted 81 US utility patents between 2015 and 2022, placing Clearsign Combustion Corporation at rank #4,371 across all assignees tracked by PlainPatent. This portfolio spans 42 distinct Cooperative Patent Classification (CPC) subclasses, averaging 30.3 claims per patent with primary concentration in F23C (METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  ; A CARRIER GAS OR; AIR). As a US Corporation, Clearsign Combustion Corporation is one of the more focused assignees in the PatentsView dataset. By volume, Clearsign sits between Arper S.p.a. (81 patents, rank #4,367) and Consolidated Nuclear Security, Llc (81 patents, rank #4,375) - the closest US assignees by grant volume. The composite Innovation Score of 53.5/100 blends portfolio volume, filing velocity, technology breadth, and claim depth into a single comparable measure drawn directly from USPTO PatentsView records.

Filing cadence tells the strategic story. Between 2020 and 2025 the company received 4 grants, compared with 77 in the 2015–2019 window, a -95% shift in five-year velocity. A cooling filing rate may reflect portfolio consolidation, shifting priorities, or reduced R&D throughput. The US Corporation classification further shapes interpretation, since corporate, government, and individual filers pursue patents for materially different reasons.

Claim depth and technology breadth together indicate competitive posture. Clearsign Combustion Corporation's 30.3 average claims per patent reflects complex, broadly scoped inventions that are difficult for competitors to design around, while a multi-domain presence across 42 subclasses balances depth with breadth. Combined with portfolio volume, these signals let analysts, investors, and licensing professionals benchmark Clearsign Combustion Corporation against peers pursuing similar technology classes.

Who files at Clearsign's volume?

Granted US patents 2015–2025 versus its nearest-ranked assignees by volume, this company marked ◀

patents

What this shows Clearsign holds 81 patents at rank #4,371, shown against the 8 assignees closest to it in grant volume rather than the industry's largest filers.

Source USPTO PatentsView, granted utility patents As of 2015–2025

Companies ranked near Clearsign

By rank, the assignees closest to #4,371 in granted patent volume.

Leaders in F23C (Methods OR Apparatus FOR Combustion Using Fluid FUEL OR S…)

Other assignees with the most granted patents in Clearsign's primary technology class.

Clearsign's Innovation Score vs. every tracked assignee

Composite of portfolio volume, filing velocity, technology breadth, and claim depth (0–100)

53 Top 9% higher than 91% of 50,000 US assignees

0–10: 687 US assignees (1%). Below this entry. 10–20: 2,527 US assignees (5%). Below this entry. 20–30: 13,162 US assignees (26%). Below this entry. 30–40: 15,294 US assignees (31%). Below this entry. 40–50: 11,491 US assignees (23%). Below this entry. 50–60: 5,058 US assignees (10%). This entry sits in this band. 60–70: 1,537 US assignees (3%). Above this entry. 70–80: 234 US assignees (0%). Above this entry. 80–90: 10 US assignees (0%). Above this entry. 90–100: 0 US assignees (0%). Above this entry. This assignee 0 100 every tracked assignee, bucketed by value

Each bar is a band; taller bars hold more US assignees. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source USPTO PatentsView, PlainPatent Innovation Score · 2015–2025

-50510152025 2015201620172018201920202022 1
USPTO utility patent grants by year · 2015–2022

Grants by year

Teal-shaded recent years (2020–present) versus the 2015–2019 baseline. Full figures in the table below.

View data table
Clearsign Combustion Corporation patent grants by year, 2015–2025
Year Patents Granted Share of Period
2015 2 2.5%
2016 21 25.9%
2017 16 19.8%
2018 22 27.2%
2019 16 19.8%
2020 3 3.7%
2022 1 1.2%

Which technologies does Clearsign Combustion Corporation patent most?

Top 15 of 42 technology areas

Patent Moat Analysis

Portfolio Volume Light
Tech Breadth Multi-domain
Claim Depth Complex
Velocity Declining

Where it ranks

Overall rank by patents

#4,371

Across all tracked assignees

Innovation Score

53.5 out of 100

View all rankings →

Data Source

USPTO PatentsView, US granted patents 2015–2025

How is Innovation Score calculated?

Frequently Asked Questions

How many patents does Clearsign Combustion Corporation hold?
Clearsign Combustion Corporation holds 81 US granted patents filed between 2015 and 2022, spanning 42 technology areas.
What is Clearsign Combustion Corporation's Innovation Score?
Clearsign Combustion Corporation has an Innovation Score of 53.5 out of 100. This composite metric weighs portfolio volume (40%), filing velocity (20%), technology breadth (25%), and claim depth (15%).
What technology areas does Clearsign Combustion Corporation focus on?
Clearsign Combustion Corporation's top technology area is F23C (METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  ; A CARRIER GAS OR; AIR) with 65 patents. The company has filed patents in 42 CPC subclasses total.
Is Clearsign Combustion Corporation's patent filing rate increasing or decreasing?
Clearsign Combustion Corporation's recent filing velocity is -95% compared to the prior five-year period. Filing activity has slowed relative to earlier years.
What does claim depth mean for Clearsign Combustion Corporation's patents?
Clearsign Combustion Corporation's patents average 30.3 claims each. This indicates complex, broadly scoped patents that are harder for competitors to design around.
How is the Clearsign Combustion Corporation patent data sourced?
All patent data comes from USPTO PatentsView, a public research dataset maintained by the United States Patent and Trademark Office covering US granted utility patents from 2015 to 2025.

How to use this portfolio

Clearsign's 81 grants land it in the top 9% by Innovation Score, but volume alone doesn't tell you where the strength sits.

  • Read that count against the largest US assignees before treating it as dominance - Clearsign ranks #4,371 of 50,000. Top 50 holders
  • Most of this portfolio concentrates in F23C - see who else leads that technology area. F23C leaders
  • Check what the four-part Innovation Score actually rewards before comparing it to another company. How the score works

Patent counts and the Innovation Score measure patenting activity, not commercial success or the legal strength of any patent. Many patents are filed defensively. Verify the status of an individual patent against official USPTO records.

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

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the USPTO PatentsView database. Consult a qualified professional before making decisions based on this data.

Read our methodology - how this data is sourced, computed, and verified.

Data sources used on this page
  • USPTO PatentsView - the disambiguated bulk patent-grant, assignee, and CPC data this page's figures are derived from. patentsview.org
  • Cooperative Patent Classification (CPC) - the joint USPTO/EPO classification scheme used to group patents by technology area. cooperativepatentclassification.org
  • USPTO Patent Public Search - the official interface to verify the status of any individual patent. ppubs.uspto.gov

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. Data current as of May 2026.