US2543899A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Keyboard
Assignee: International Business Machines Corp
•
Filing: 1945-09-21
•
Granted: 1951-03-06
•
Expires: 1965-09-21
Abstract
No abstract record available.
Inventors
- 👤 Arthur H Dickinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:52
CPC Classifications
H; H04; H04M; H04M9/00; H04M9/002; H04M9/003
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1442059A
Cited
US2014432A
Cited
US2061745A
Cited
US1976617A
Cited
US2156969A
Cited
US2174685A
Cited
US2364540A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-03-05 | 1954-09-04 | 1955-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-03-05 | 1958-09-04 | 1959-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-03-05 | 1962-09-04 | 1963-03-06 | $7700.00 | Window Closed / Lapsed |