US3468386A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Formation perforator
Assignee: HAROLD E JOHNSON
•
Filing: 1967-09-05
•
Granted: 1969-09-23
•
Expires: 1987-09-05
Abstract
No abstract record available.
Inventors
- 👤 Harold E Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:03
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/11; E21B43/116; E21B43/117
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2201290A
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US2500754A
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US2587244A
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US2725942A
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US2775304A
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US2873676A
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US2939532A
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US3270814A
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US3336759A
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US3357504A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-09-22 | 1973-03-24 | 1973-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-09-22 | 1977-03-24 | 1977-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-09-22 | 1981-03-24 | 1981-09-23 | $7700.00 | Window Closed / Lapsed |