Patent US2853944A successfully refreshed from Google Patents.
US2853944A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for perforating well casing and the like
Assignee: Borg Warner Corp
•
Filing: 1951-02-06
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Granted: 1958-09-30
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Expires: 1971-02-06
Abstract
No abstract record available.
Inventors
- 👤 Harry S Robertson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:06
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/11; E21B43/116; E21B43/117
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-29 | 1962-03-31 | 1962-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-29 | 1966-03-31 | 1966-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-29 | 1970-03-31 | 1970-09-30 | $7700.00 | Window Closed / Lapsed |