US2990148A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Airborne stairs
Assignee: Boeing Co
•
Filing: 1957-05-10
•
Granted: 1961-06-27
•
Expires: 1977-05-10
Abstract
No abstract record available.
Inventors
- 👤 Varnell L R James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:47
CPC Classifications
B; B64; B64C; B64C1/00; B64C1/24
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US305516A
Cited
US961357A
Cited
US995273A
Cited
US2531263A
Cited
US2453937A
Cited
US2558975A
Cited
US2647677A
Cited
US2812528A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-06-26 | 1964-12-26 | 1965-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-26 | 1968-12-26 | 1969-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-26 | 1972-12-26 | 1973-06-27 | $7700.00 | Window Closed / Lapsed |