US3421149A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data processing system having a bidirectional storage medium
Assignee: AT&T Inc
•
Filing: 1966-04-06
•
Granted: 1969-01-07
•
Expires: 1986-04-06
Abstract
No abstract record available.
Inventors
- 👤 Ernest R Kretzmer
- 👤 Paul Mecklenburg
- 👤 Donald W Rice
- 👤 William Ryan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:53
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US3302176A
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US3293616A
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US3328763A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-07 | 1972-07-08 | 1973-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-07 | 1976-07-08 | 1977-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-07 | 1980-07-08 | 1981-01-07 | $7700.00 | Window Closed / Lapsed |