Patent US2877977A successfully refreshed from Google Patents.
US2877977A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Well control equipment
Assignee: Cooper Industries LLC
•
Filing: 1956-04-06
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Granted: 1959-03-17
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Expires: 1976-04-06
Abstract
No abstract record available.
Inventors
- 👤 Allen Herbert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:12
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/03; E21B33/06; E21B33/061; E21B33/062
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USRE20631E
Cited
US1586923A
Cited
US1560763A
Cited
US2192805A
Cited
US2194258A
Cited
US2243340A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-03-16 | 1962-09-15 | 1963-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-03-16 | 1966-09-15 | 1967-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-03-16 | 1970-09-15 | 1971-03-17 | $7700.00 | Window Closed / Lapsed |