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US3544994A
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Assignee: International Business Machines Corp
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Filing: 1967-10-02
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Granted: 1970-12-01
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Expires: 1987-10-02
Abstract
No abstract record available.
Inventors
- 👤 Charles C Hanson
- 👤 Joseph P L Ho
- 👤 Lawrence P Segar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:44
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/50
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3239831A
Cited
US3325805A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-11-30 | 1974-06-01 | 1974-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-11-30 | 1978-06-01 | 1978-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-11-30 | 1982-06-01 | 1982-12-01 | $7700.00 | Window Closed / Lapsed |