Where does China National Offshore OIL Corporation rank among US patent assignees?

According to USPTO PatentsView (2015–2025 granted utility patents), China National Offshore OIL Corporation ranks #12,386 of 49,997 assignees by granted-patent volume, the same sort as the companies listing and top-holders ranking. See /methodology/#corpus-placement.

How many patents does China National Offshore OIL Corporation hold?

China National Offshore OIL Corporation holds 24 US utility patents granted between 2015 and 2025, spanning 26 technology areas.

What is China National Offshore OIL Corporation's Innovation Score?

China National Offshore OIL Corporation has an Innovation Score of 40.3 out of 100 (top 36% of the corpus). This composite metric weighs portfolio volume (40%), grant velocity (20%), technology breadth (25%), and claim depth (15%).

Is China National Offshore OIL Corporation's patent grant rate increasing or decreasing?

China National Offshore OIL Corporation's recent grant velocity is -25% compared to the prior five-year period (grant years, not application filing dates). Grant activity has slowed relative to earlier years.

What does claim depth mean for China National Offshore OIL Corporation's patents?

China National Offshore OIL Corporation's patents average 12.5 claims each. This is an aggregate descriptive count from the grant record; it does not establish claim scope, legal strength, enforceability, or design-around risk.

How is the China National Offshore OIL 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.

USPTO 2015–2025 USPTO PatentsView Foreign Corporation

China National Offshore OIL Corporation

Q: What technology areas does China National Offshore OIL Corporation focus on?

China National Offshore OIL Corporation's top technology area is E21B (Earth OR Rock DRILLING; Obtaining OIL, GAS, Water, Soluble OR Meltable Materials OR A Slurry OF Minerals From Wells) with 14 patents, ranking #261 of 1,363 assignees active in that subclass. Grants appear in 26 CPC subclasses total.

USPTO PatentsView assignee record - 24 granted patents across 26 technology areas, recorded in grant years 2015–2025. Grant-trend analysis is cross-referenced to USPTO Patent Public Search; it does not measure application filings, current R&D, or legal strength. Primary class: E21B (Earth OR Rock DRILLING; Obtaining OIL, GAS, Water, Soluble OR Meltable Materials OR A Slurry OF Minerals From Wells).

Compiled by PlainPatent · May 15, 2026

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The verdict

According to USPTO PatentsView, China ranks #12,386 of 49,997 tracked US assignees by granted-patent volume, with 24 patents across 26 technology areas.

#12,386
of 49,997 US assignees by volume: Top 36%
by Innovation Score (40.3/100): 12.5
avg claims per patent: -25%
grant velocity, last 5 yrs

USPTO PatentsView assignee plate

Corpus R12386 · Foreign Corporation #12,386 · 24 grants

GRANTS-SMALL · UPPER-Q · PHOTO-FINISH · CPC-FOCUS · INNOV-PAR · CLAIMS-RICH · TYPE-FRNCORP · VEL-DOWN · BOOK-FULL

GRANTS-SMALL 24 grants
UPPER-Q #12,386/49,997
PHOTO-FINISH Burton
CPC-FOCUS E21B · 26 areas
INNOV-PAR 40.3/100
CLAIMS-RICH 12.5 claims/avg
TYPE-FRNCORP Foreign Corp
VEL-DOWN -25% vel
BOOK-FULL 10/10 fields

Nearest grant-volume peer: Burton Technologies, LLC (±0 grants)

Instrument codes from this assignee’s USPTO PatentsView grant sheet: volume band, corpus rank, photo-finish peer, lead CPC, Innovation Score, claim depth, assignee type, velocity, and book completeness. Not a USPTO rating of patent strength.

How China’s 40.3 Innovation Score adds up

The same four weighted components behind every Innovation Score on PlainPatent: portfolio volume, grant velocity, technology breadth, and claim depth.

Volume 11.1 pts (28%) Velocity 3.7 pts (9%) Breadth 18.0 pts (45%) Claim depth 7.5 pts (19%)

Qualcomm Incorporated · highest

85
China National… · this assignee

40
3D Lighting… · lowest

7

What this shows China's Innovation Score is 40.3/100 (top 36% of the PatentsView-derived corpus). The chart places that score against the nearest Innovation Score peers plus corpus poles, not a reprint of the volume ranking.

Does more volume mean deeper claims for China?

Each dot is one of China’s 8 nearest volume peers (same corpus rank neighbourhood as the chart above), placed by total granted patents (horizontal) against average claims per patent (vertical). China’s own 12.5 claims/patent is at or below the 15.1 median for these volume peers. Volume here does not track with deeper claims; several lower-volume peers claim more thoroughly per patent.

China vs its 8 nearest volume peers: granted patents vs average claims per patent. Source: USPTO PatentsView.

Where China's grants concentrate

China National Offshore OIL Corporation is a focused PatentsView assignee: 26 CPC subclasses with 58.3% of grants classified under E21B (Earth OR Rock DRILLING; Obtaining OIL, GAS, Water, Soluble OR Meltable Materials OR A Slurry OF Minerals From Wells). Peak complete grant year is 2019 (5 grants) versus a trough of 1 in 2015. By volume, China sits between Burton Technologies, LLC and Crrc Tangshan Co., Ltd..

China's three-year grant acceleration

China National Offshore OIL Corporation shows 5 grants in 2022–2024 against only 9 in 2019–2021. That prior window is too thin for a growth multiple (rename and spin-out assignees look artificially high when the baseline is near zero), so PlainPatent withholds a ranked acceleration claim here.

Burton

24
Calitor Sciences

24
Camfil USA

24
Centrillion Techn…

24
Claas Saulgau

24
Constellium Neuf-…

24
Copreci S COOP

24
Crrc Tangshan

24
China National Of… ◀

24

What this shows China holds 24 patents at rank #12,382, shown against the 8 assignees closest to it in grant volume rather than the industry's largest filers.

Companies ranked near China

By rank, the assignees closest to #12,382 in granted patent volume.

Leaders in E21B (Earth OR Rock Drilling)

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

China's Innovation Score vs. every tracked assignee

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

40 Top 36% higher than 64% of 49,997 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

China National Offshore OIL Corporation patent grants by year, 2015–2025
Year	Patents Granted	Share of Period
2015	1	4.2%
2016	3	12.5%
2018	3	12.5%
2019	5	20.8%
2020	1	4.2%
2021	3	12.5%
2023	2	8.3%
2024	3	12.5%
2025partial year	3	12.5%

Which technologies does China National Offshore OIL Corporation patent most?

E21B - Earth OR Rock DRILLING; Obtaining OIL, GAS, Water, Soluble OR Meltable Materials OR A Slurry OF Minerals From Wells 14

G01N - Investigating OR Analysing Materials BY Determining Their Chemical OR Physical Properties 5

G01V - GEOPHYSICS; Gravitational MEASUREMENTS; Detecting Masses OR OBJECTS; Tags 3

F16L - PIPES; Joints OR Fittings FOR PIPES; Supports FOR Pipes, Cables OR Protective TUBING; Means FOR Thermal Insulation IN General 3

B63B - Ships OR Other Waterborne VESSELS; Equipment FOR Shipping 3

C09K - Materials FOR Miscellaneous Applications, NOT Provided FOR Elsewhere 2

G01B - Measuring Length, Thickness OR Similar Linear DIMENSIONS; Measuring ANGLES; Measuring AREAS; Measuring Irregularities OF Surfaces OR Contours 2

G01D - Measuring NOT Specially Adapted FOR A Specific VARIABLE; Arrangements FOR Measuring TWO OR More Variables NOT Covered IN A Single Other SUBCLASS; Tariff Metering APPARATUS; Measuring OR Testing NOT Otherwise Provided FOR 2

C23F - Non-mechanical Removal OF Metallic Material From Surface ; Inhibiting Corrosion OF Metallic Material OR Incrustation IN GENERAL; Multi-step Processes FOR Surface Treatment OF Metallic Material Involving AT Least ONE Process Provided FOR IN Class C23 AND AT Least ONE Process Covered BY Subclass C21d 1

C10G - Cracking Hydrocarbon OILS; Production OF Liquid Hydrocarbon Mixtures, e.g. BY Destructive Hydrogenation, Oligomerisation, Polymerisation ; Recovery OF Hydrocarbon Oils From Oil-shale, Oil-sand, OR GASES; Refining Mixtures Mainly Consisting OF HYDROCARBONS; Reforming OF NAPHTHA; Mineral Waxes 1

B01D - Separation 1

F17C - Vessels FOR Containing OR Storing Compressed, Liquefied OR Solidified GASES; Fixed-capacity GAS-HOLDERS; Filling Vessels With, OR Discharging From Vessels, Compressed, Liquefied, OR Solidified Gases 1

G05D - Systems FOR Controlling OR Regulating Non-electric Variables 1

F15B - Systems Acting BY Means OF Fluids IN GENERAL; Fluid-pressure Actuators, e.g. SERVOMOTORS; Details OF Fluid-pressure Systems, NOT Otherwise Provided FOR 1

G06N - Computing Arrangements Based ON Specific Computational Models 1

Top 15 of 26 technology areas

More on this record

Data Source

USPTO PatentsView, US granted patents 2015–2025

View all rankings → How is Innovation Score calculated?

What to do with this data

China National Offshore OIL Corporation's patent record in context - here's where to go next.

China National Offshore OIL Corporation's lead technology class is E21B (Earth OR Rock DRILLING; Obtaining OIL, GAS, Water, Soluble OR Meltable Materials OR A Slurry OF Minerals From Wells), 58.3% of its portfolio - see every assignee active in that class. Explore E21B
Ranked #12,386 of 49,997 tracked assignees by patent volume - see the full leaderboard. See the ranking
Compare China National Offshore OIL Corporation against Burton Technologies, LLC, an assignee filing at a similar volume. Compare portfolios
Innovation Score of 40.3/100 blends volume, velocity, technology breadth, and claim depth. How it's calculated

Figures reflect USPTO PatentsView grant data through May 2026; pending applications not yet granted are not counted.

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

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 by PlainPatent, US Patent Intelligence Editorial Process · 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.