Patent US5391557A successfully refreshed from Google Patents.
US2641320A
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Composite keyboard
Assignee: International Business Machines Corp
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Filing: 1949-07-13
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Granted: 1953-06-09
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Expires: 1969-07-13
Abstract
No abstract record available.
Inventors
- 👤 Reynold B Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:29
CPC Classifications
B; B41; B41B; B41B25/00; G; G06; G06F; G06F3/00; G06F3/01; G06F3/02; G06F3/0202; G06F3/0216; G06F3/0219; G06F3/023; G06F3/0233; G06F3/0234; G06F3/0235; H; H04; H04M; H04M1/00; H04M1/02; H04M1/23
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) | 1956-06-08 | 1956-12-08 | 1957-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-08 | 1960-12-08 | 1961-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-08 | 1964-12-08 | 1965-06-09 | $7700.00 | Window Closed / Lapsed |