Patent US2979955A successfully refreshed from Google Patents.
US2979955A
Expired / Lapsed
US
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Pressure responsive systems
Assignee: Schlumberger Well Surveying Corp
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Filing: 1957-04-12
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Granted: 1961-04-18
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Expires: 1977-04-12
Abstract
No abstract record available.
Inventors
- 👤 Paul R Shepler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:51
CPC Classifications
G; G01; G01L; G01L13/00; G01L13/02; G01L13/023; G01F; G01F1/00; G01F1/05; G01F1/34; G01F1/36; G01F1/38; G01F1/383; G01L9/00; G01L9/0033; G01L9/0036
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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FR1097349A
Cited
FR1126505A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-17 | 1964-10-17 | 1965-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-17 | 1968-10-17 | 1969-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-17 | 1972-10-17 | 1973-04-18 | $7700.00 | Window Closed / Lapsed |