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Patent US1377981A successfully refreshed from Google Patents.
US3382831A
Expired / Lapsed
US
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Torpedo drag reduction apparatus
Assignee: United States Department of the Navy
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Filing: 1967-08-31
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Granted: 1968-05-14
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Expires: 1987-08-31
Abstract
No abstract record available.
Inventors
- 👤 William F Madison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:47
CPC Classifications
B; B63; B63B; B63B1/00; B63B1/32; B63B1/34; F; F42; F42B; F42B19/00; F42B19/12; F42B19/125; Y; Y02; Y02T; Y02T70/00; Y02T70/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-05-14 | 1971-11-13 | 1972-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-05-14 | 1975-11-13 | 1976-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-05-14 | 1979-11-13 | 1980-05-14 | $7700.00 | Window Closed / Lapsed |