US3467220A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stairway construction
Assignee: Individual
•
Filing: 1967-03-20
•
Granted: 1969-09-16
•
Expires: 1987-03-20
Abstract
No abstract record available.
Inventors
- 👤 Frank Burchard Smith
- 👤 Stephen Brian Harley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:39
CPC Classifications
E; E04; E04F; E04F11/00; E04F11/02; E04F11/022; E04F11/025; E04F11/028; E04F11/104
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) | 1972-09-15 | 1973-03-17 | 1973-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-09-15 | 1977-03-17 | 1977-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-09-15 | 1981-03-17 | 1981-09-16 | $7700.00 | Window Closed / Lapsed |