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US3521041A
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Assignee: International Business Machines Corp
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Filing: 1967-07-19
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Granted: 1970-07-21
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Expires: 1987-07-19
Abstract
No abstract record available.
Inventors
- 👤 Richard Van Blerkom
- 👤 Don G Freeman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:40
CPC Classifications
G; G06; G06F; G06F7/00; G06F7/38; G06F7/48; G06F7/52; G06F7/523; G06F7/533; G06F7/5334; H; H03; H03H; H03H17/00; H03H17/02; H03H17/06; H03H17/0223; H03H17/0227; H03H17/023; H03H2017/0232
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) | 1973-07-20 | 1974-01-19 | 1974-07-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-20 | 1978-01-19 | 1978-07-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-20 | 1982-01-19 | 1982-07-21 | $7700.00 | Window Closed / Lapsed |