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US2867779A
Expired / Lapsed
US
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Seismograph filter systems
Assignee: Gulf Research and Development Co
•
Filing: 1955-11-14
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Granted: 1959-01-06
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Expires: 1975-11-14
Abstract
No abstract record available.
Inventors
- 👤 Bardeen Thomas
- 👤 Irving C Zacher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:00
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/01; H03H7/0153; H03H7/0161; H03H7/17; H03H7/1741; H03H7/175; H03H7/1775; G; G01; G01V; G01V1/00; G01V1/16; G01V1/162; G01V1/164
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2276873A
Cited
US2661459A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-01-05 | 1962-07-07 | 1963-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-01-05 | 1966-07-07 | 1967-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-01-05 | 1970-07-07 | 1971-01-06 | $7700.00 | Window Closed / Lapsed |