US2807993A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ventilating ceiling construction
Assignee: AIRSON Co Inc
•
Filing: 1955-01-03
•
Granted: 1957-10-01
•
Expires: 1975-01-03
Abstract
No abstract record available.
Inventors
- 👤 Walter M Ericson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:11
CPC Classifications
F; F24; F24F; F24F7/00; F24F7/04; F24F7/06; F24F7/10; E; E04; E04B; E04B9/00; E04B9/02; E04B9/22; E04B9/24; E04B9/247
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1928798A
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GB377634A
Cited
US2180945A
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US2221001A
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US2251663A
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US2270268A
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US2537315A
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US2585666A
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US2667667A
Cited
US2692547A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-30 | 1961-04-01 | 1961-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-30 | 1965-04-01 | 1965-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-30 | 1969-04-01 | 1969-10-01 | $7700.00 | Window Closed / Lapsed |