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US2818858A
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US
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Underwater breathing apparatus
Assignee: OLD DOMINION RES AND DEV CORP
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Filing: 1954-03-12
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Granted: 1958-01-07
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Expires: 1974-03-12
Abstract
No abstract record available.
Inventors
- 👤 Carl H Holm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:33
CPC Classifications
B; B63; B63C; B63C9/00; B63C9/08; B63C9/11; B63C9/125; B63C11/00; B63C11/02; B63C11/18; B63C11/22; B63C11/2236; B63C2011/026
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) | 1961-01-06 | 1961-07-08 | 1962-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-06 | 1965-07-08 | 1966-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-06 | 1969-07-08 | 1970-01-07 | $7700.00 | Window Closed / Lapsed |