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US2500294A
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Assignee: International Business Machines Corp
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Filing: 1947-08-13
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Granted: 1950-03-14
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Expires: 1967-08-13
Abstract
No abstract record available.
Inventors
- 👤 Byron E Phelps
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 18:44
CPC Classifications
H; H03; H03K; H03K23/00; H03K23/82
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) | 1953-03-13 | 1953-09-12 | 1954-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-03-13 | 1957-09-12 | 1958-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-03-13 | 1961-09-12 | 1962-03-14 | $7700.00 | Window Closed / Lapsed |