Patent US2900977A successfully refreshed from Google Patents.
US2900977A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Underwater breathing apparatus
Assignee: Individual
•
Filing: 1955-05-31
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Granted: 1959-08-25
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Expires: 1975-05-31
Abstract
No abstract record available.
Inventors
- 👤 De Loss L Marsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:19
CPC Classifications
B; B63; B63C; B63C11/00; B63C11/02; B63C11/18; B63C11/22; B63C11/24
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) | 1962-08-24 | 1963-02-23 | 1963-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-24 | 1967-02-23 | 1967-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-24 | 1971-02-23 | 1971-08-25 | $7700.00 | Window Closed / Lapsed |