Patent US2817121A successfully refreshed from Google Patents.
US2817121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grandstands
Assignee: Individual
•
Filing: 1951-10-09
•
Granted: 1957-12-24
•
Expires: 1971-10-09
Abstract
No abstract record available.
Inventors
- 👤 Mackintosh Charles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:34
CPC Classifications
E; E04; E04H; E04H3/00; E04H3/10; E04H3/12; E04H3/126
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
AT29297B
Cited
US1067440A
Cited
US2054960A
Cited
US1811708A
Cited
US2018887A
Cited
US2030776A
Cited
US2176731A
Cited
US2147564A
Cited
US2245825A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-12-23 | 1961-06-24 | 1961-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-23 | 1965-06-24 | 1965-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-23 | 1969-06-24 | 1969-12-24 | $7700.00 | Window Closed / Lapsed |