US1800903A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Incandescent lamp
Assignee: AT&T Inc
•
Filing: 1929-03-30
•
Granted: 1931-04-14
•
Expires: 1949-03-30
Abstract
No abstract record available.
Inventors
- 👤 Ramsey Ernest Glen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:12
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/20; G03B21/2006; G03B21/2013; G03B21/202
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) | 1934-04-13 | 1934-10-13 | 1935-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-04-13 | 1938-10-13 | 1939-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-04-13 | 1942-10-13 | 1943-04-14 | $7700.00 | Window Closed / Lapsed |