US2872940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical control and indicating system
Assignee: Hydril LLC
•
Filing: 1956-10-17
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Granted: 1959-02-10
•
Expires: 1976-10-17
Abstract
No abstract record available.
Inventors
- 👤 George E Lewis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:28
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/03; E21B33/06; Y; Y10; Y10T; Y10T137/00; Y10T137/8158; Y10T137/8225; Y10T137/8242
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2528898A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-02-09 | 1962-08-11 | 1963-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-02-09 | 1966-08-11 | 1967-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-02-09 | 1970-08-11 | 1971-02-10 | $7700.00 | Window Closed / Lapsed |