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Patent US3489375A successfully refreshed from Google Patents.
US3489375A
Expired / Lapsed
US
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Variable lifting surface craft
Assignee: RICHARD R TRACY
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Filing: 1967-11-21
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Granted: 1970-01-13
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Expires: 1987-11-21
Abstract
No abstract record available.
Inventors
- 👤 Richard R Tracy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:52
CPC Classifications
B; B64; B64C; B64C3/00; B64C3/38; B64C3/40
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1009770A
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US1018413A
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US2354116A
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US2673047A
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US2941752A
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FR1168938A
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US2941762A
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US3288400A
Cited
US3405280A
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US3330501A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-01-12 | 1973-07-14 | 1974-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-01-12 | 1977-07-14 | 1978-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-01-12 | 1981-07-14 | 1982-01-13 | $7700.00 | Window Closed / Lapsed |