US818413A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined metal core vent and support.
Assignee: ARTHUR B UNDERHILL
•
Filing: 1904-03-03
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Granted: 1906-04-24
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Expires: 1924-03-03
Abstract
No abstract record available.
Inventors
- 👤 Henry C Caldwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:08
CPC Classifications
B; B22; B22C; B22C9/00; B22C9/10; B22C9/108
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1909-04-23 | 1909-10-23 | 1910-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1913-04-23 | 1913-10-23 | 1914-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1917-04-23 | 1917-10-23 | 1918-04-24 | $7700.00 | Window Closed / Lapsed |