USPTO 2015–2025 USPTO PatentsView Foreign Corporation

NGK Spark PLUG Co., Ltd.

USPTO PatentsView assignee record - 823 granted patents across 119 technology areas, active 2015–2025. Filing-trend and competitive-moat analysis cross-referenced to USPTO Patent Public Search. Primary class: H01T (SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES).

Compiled byPlainPatent Editorial, US Patent Intelligence Editorial Team · May 15, 2026

Explore the portfolio See the ranking

823

Total patents granted

119

CPC technology areas

7.6

Avg claims per patent

-59%

5-year filing velocity

The verdict

NGK holds 823 US patents across 119 technology areas, rank #547 of 50,000 tracked assignees.

#547
of 50,000 US assignees by volume: Top 8%
by Innovation Score (54.3/100): 7.6
avg claims per patent: -59%
filing velocity, last 5 yrs

Portfolio overview

NGK Spark PLUG Co., Ltd. has been granted 823 US utility patents between 2015 and 2025, placing NGK Spark PLUG Co., Ltd. at rank #547 across all assignees tracked by PlainPatent. This portfolio spans 119 distinct Cooperative Patent Classification (CPC) subclasses, averaging 7.6 claims per patent with primary concentration in H01T (SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES). As a Foreign Corporation, NGK Spark PLUG Co., Ltd. is one of the broader-portfolio assignees in the PatentsView dataset. By volume, NGK sits between Silicon Laboratories Inc. (825 patents, rank #543) and Sony Mobile Communications Inc. (815 patents, rank #551) - the closest US assignees by grant volume. The composite Innovation Score of 54.3/100 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 239 grants, compared with 584 in the 2015–2019 window, a -59% shift in five-year velocity. A cooling filing rate may reflect portfolio consolidation, shifting priorities, or reduced R&D throughput. The Foreign 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. NGK Spark PLUG Co., Ltd.'s 7.6 average claims per patent suggests focused, narrowly drawn claims typical of single-invention filings, while a diversified footprint across 100+ CPC subclasses spreads risk across many technology fronts. Combined with portfolio volume, these signals let analysts, investors, and licensing professionals benchmark NGK Spark PLUG Co., Ltd. against peers pursuing similar technology classes.

Silicon Laborator…

825
E Ink Holdings

824
Kaneka

824
Industry-academic…

823
NGK Spark PLUG ◀

823
National Institut…

822
Mitutoyo

820
Saint-gobain Glas…

820
Sony Mobile Commu…

815

What this shows NGK holds 823 patents at rank #547, shown against the 8 assignees closest to it in grant volume rather than the industry's largest filers.

Companies ranked near NGK

By rank, the assignees closest to #547 in granted patent volume.

Leaders in H01T (Spark GAPS)

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

NGK's Innovation Score vs. every tracked assignee

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

54 Top 8% higher than 92% of 50,000 US assignees

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

USPTO utility patent grants by year · 2015–2025

Grants by year

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

View data table

NGK Spark PLUG Co., Ltd. patent grants by year, 2015–2025
Year	Patents Granted	Share of Period
2015	111	13.5%
2016	123	14.9%
2017	116	14.1%
2018	122	14.8%
2019	112	13.6%
2020	102	12.4%
2021	68	8.3%
2022	35	4.3%
2023	29	3.5%
2024	4	0.5%
2025	1	0.1%

Which technologies does NGK Spark PLUG Co., Ltd. patent most?

H01T - SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES 304

G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES 220

H01L - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10 89

H05K - PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS 71

F02P - IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES 62

C04B - LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE ; CERAMICS ; REFRACTORIES; TREATMENT OF NATURAL STONE 59

F01N - GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES 52

Y10T - TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION 46

Y02T - CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION 41

G01M - TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR 41

F23Q - IGNITION ; EXTINGUISHING-DEVICES 35

Y02E - REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION 32

H05B - ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL 32

F02D - CONTROLLING COMBUSTION ENGINES 30

H01M - PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY 29

Top 15 of 119 technology areas

Patent Moat Analysis

Portfolio Volume Moderate

Tech Breadth Diversified

Claim Depth Simple

Velocity Declining

Where it ranks

Overall rank by patents

#547

Across all tracked assignees

Innovation Score

54.3 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 NGK Spark PLUG Co., Ltd. hold?

NGK Spark PLUG Co., Ltd. holds 823 US granted patents filed between 2015 and 2025, spanning 119 technology areas.

What is NGK Spark PLUG Co., Ltd.'s Innovation Score?

NGK Spark PLUG Co., Ltd. has an Innovation Score of 54.3 out of 100. This composite metric weighs portfolio volume (40%), filing velocity (20%), technology breadth (25%), and claim depth (15%).

What technology areas does NGK Spark PLUG Co., Ltd. focus on?

NGK Spark PLUG Co., Ltd.'s top technology area is H01T (SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES) with 304 patents. The company has filed patents in 119 CPC subclasses total.

Is NGK Spark PLUG Co., Ltd.'s patent filing rate increasing or decreasing?

NGK Spark PLUG Co., Ltd.'s recent filing velocity is -59% compared to the prior five-year period. Filing activity has slowed relative to earlier years.

What does claim depth mean for NGK Spark PLUG Co., Ltd.'s patents?

NGK Spark PLUG Co., Ltd.'s patents average 7.6 claims each. This is relatively simple claim structure, typical for focused inventions.

How is the NGK Spark PLUG Co., Ltd. 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

NGK's 823 grants land it in the top 8% 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 - NGK ranks #547 of 50,000. Top 50 holders
Most of this portfolio concentrates in H01T - see who else leads that technology area. H01T 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

Compiled byPlainPatent Editorial, US Patent Intelligence Editorial Team · May 15, 2026

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.