Where does China Oilfield Services Limited rank among US patent assignees?

According to USPTO PatentsView (2015–2025 granted utility patents), China Oilfield Services Limited ranks #13,917 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 Oilfield Services Limited hold?

China Oilfield Services Limited holds 21 US utility patents granted between 2016 and 2025, spanning 18 technology areas.

What is China Oilfield Services Limited's Innovation Score?

China Oilfield Services Limited has an Innovation Score of 41.1 out of 100 (top 34% of the corpus). This composite metric weighs portfolio volume (40%), grant velocity (20%), technology breadth (25%), and claim depth (15%).

Is China Oilfield Services Limited's patent grant rate increasing or decreasing?

China Oilfield Services Limited's recent grant velocity is +13% compared to the prior five-year period (grant years, not application filing dates). The company is maintaining or growing its granted-patent output.

What does claim depth mean for China Oilfield Services Limited's patents?

China Oilfield Services Limited's patents average 12.7 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 Oilfield Services Limited 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 Oilfield Services Limited

Q: What technology areas does China Oilfield Services Limited focus on?

China Oilfield Services Limited'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 18 patents, ranking #203 of 1,363 assignees active in that subclass. Grants appear in 18 CPC subclasses total.

USPTO PatentsView assignee record - 21 granted patents across 18 technology areas, recorded in grant years 2016–2025. 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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Explore the portfolio See the ranking

The verdict

According to USPTO PatentsView, China ranks #13,917 of 49,997 tracked US assignees by granted-patent volume, with 21 patents across 18 technology areas.

#13,917
of 49,997 US assignees by volume: Top 34%
by Innovation Score (41.1/100): 12.7
avg claims per patent: +13%
grant velocity, last 5 yrs

USPTO PatentsView assignee plate

Corpus R13917 · Foreign Corporation #13,917 · 21 grants

GRANTS-SMALL · MID-PACK · PHOTO-FINISH · CPC-FOCUS · INNOV-PAR · CLAIMS-RICH · TYPE-FRNCORP · VEL-UP · BOOK-FULL

GRANTS-SMALL 21 grants
MID-PACK #13,917/49,997
PHOTO-FINISH Celeno Communication…
CPC-FOCUS E21B · 18 areas
INNOV-PAR 41.1/100
CLAIMS-RICH 12.7 claims/avg
TYPE-FRNCORP Foreign Corp
VEL-UP +13% vel
BOOK-FULL 10/10 fields

Nearest grant-volume peer: Celeno Communications (ISRAEL) Ltd. (±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 41.1 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 10.7 pts (26%) Velocity 7.8 pts (19%) Breadth 15.0 pts (36%) Claim depth 7.6 pts (18%)

Qualcomm Incorporated · highest

85
China Oilfield… · this assignee

41
3D Lighting… · lowest

7

What this shows China's Innovation Score is 41.1/100 (top 34% 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 12.7 claims/patent is ABOVE the 10.3 median for these volume peers. More thorough claims than most filers at this scale, not just more of them.

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

Where China's grants concentrate

China Oilfield Services Limited is a focused PatentsView assignee: 18 CPC subclasses with 85.7% 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 (4 grants) versus a trough of 1 in 2016. By volume, China sits between Celeno Communications (ISRAEL) Ltd. and Collibra Belgium BV.

China's three-year grant acceleration

China Oilfield Services Limited shows 7 grants in 2022–2024 against only 6 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.

Celeno Communicat…

21
Centaur Technology

21
CG BIO

21
Changchun Institu…

21
Chirogate Interna…

21
Cinogy

21
Classic Home & Ga…

21
Collibra Belgium…

21
China Oilfield Se… ◀

21

What this shows China holds 21 patents at rank #13,908, 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 #13,908 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)

41 Top 34% higher than 66% 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 · 2016–2025

Grants by year

Teal-shaded recent years (2020–present) versus the 2016–2019 baseline. Full figures in the table below.

View data table

China Oilfield Services Limited patent grants by year, 2015–2025
Year	Patents Granted	Share of Period
2016	1	4.8%
2018	3	14.3%
2019	4	19.0%
2021	2	9.5%
2023	3	14.3%
2024	4	19.0%
2025partial year	4	19.0%

Which technologies does China Oilfield Services Limited patent most?

E21B - Earth OR Rock DRILLING; Obtaining OIL, GAS, Water, Soluble OR Meltable Materials OR A Slurry OF Minerals From Wells 18

G01N - Investigating OR Analysing Materials BY Determining Their Chemical OR Physical Properties 4

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

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

C09K - Materials FOR Miscellaneous Applications, NOT Provided FOR Elsewhere 1

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

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

F16L - PIPES; Joints OR Fittings FOR PIPES; Supports FOR Pipes, Cables OR Protective TUBING; Means FOR Thermal Insulation IN General 1

G01L - Measuring Force, Stress, Torque, Work, Mechanical Power, Mechanical Efficiency, OR Fluid Pressure 1

G01H - Measurement OF Mechanical Vibrations OR Ultrasonic, Sonic OR Infrasonic Waves 1

G10K - Sound-producing DEVICES; Methods OR Devices FOR Protecting Against, OR FOR Damping, Noise OR Other Acoustic Waves IN GENERAL; Acoustics NOT Otherwise Provided FOR 1

H02K - Dynamo-electric Machines 1

F04B - Positive-displacement Machines FOR LIQUIDS; Pumps 1

Top 15 of 18 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 Oilfield Services Limited's patent record in context - here's where to go next.

China Oilfield Services Limited'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), 85.7% of its portfolio - see every assignee active in that class. Explore E21B
Ranked #13,917 of 49,997 tracked assignees by patent volume - see the full leaderboard. See the ranking
Compare China Oilfield Services Limited against Celeno Communications (ISRAEL) Ltd., an assignee filing at a similar volume. Compare portfolios
Innovation Score of 41.1/100 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.