- All sections
- E - Fixed constructions
- E21B - Earth or rock drilling; obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B 19/09 - Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods specially adapted for drilling underwater formations from a floating support using heave compensators supporting the drill string
Patent holdings for IPC class E21B 19/09
Total number of patents in this class: 200
10-year publication summary
26
|
28
|
21
|
11
|
13
|
11
|
6
|
3
|
7
|
0
|
2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
Owner |
All patents
|
This class
|
---|---|---|
Itrec B.V. | 494 |
32 |
Mhwirth AS | 125 |
10 |
Halliburton Energy Services, Inc. | 20419 |
7 |
Castor Drilling Solution AS | 7 |
7 |
IFP Energies Nouvelles | 2824 |
7 |
Schlumberger Canada Limited | 7147 |
4 |
Cameron International Corporation | 1322 |
4 |
Ensco International Incorporated | 55 |
4 |
Grant Prideco, Inc. | 407 |
4 |
Noble Drilling A/S | 48 |
4 |
Schlumberger Technology Corporation | 10241 |
3 |
Schlumberger Technology B.v. | 5068 |
3 |
Schlumberger Holdings Limited | 2867 |
3 |
Weatherford Technology Holdings, LLC | 2105 |
3 |
Smith International, Inc. | 741 |
3 |
Cameron Sense AS | 3 |
3 |
Depro AS | 10 |
3 |
Electrical Subsea & Drilling AS | 42 |
3 |
Nabors Drilling Technologies USA, Inc. | 547 |
3 |
National Oilwell Varco, L.P. | 1628 |
3 |
Other owners | 87 |