US2481581A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extension stepladder
Assignee: Individual
•
Filing: 1945-12-17
•
Granted: 1949-09-13
•
Expires: 1965-12-17
Abstract
No abstract record available.
Inventors
- 👤 Ehnhuus Hartvig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:32
CPC Classifications
E; E06; E06C; E06C7/00; E06C7/42; E06C7/44; E06C1/00; E06C1/02; E06C1/38; E06C1/39; E06C1/393; Y; Y10; Y10T; Y10T403/00; Y10T403/32; Y10T403/32254; Y10T403/32426; Y10T403/71; Y10T403/7152
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) | 1952-09-12 | 1953-03-14 | 1953-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-09-12 | 1957-03-14 | 1957-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-09-12 | 1961-03-14 | 1961-09-13 | $7700.00 | Window Closed / Lapsed |