Patent US2325295A successfully refreshed from Google Patents.
US3489622A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making high frequency transistors
Assignee: International Business Machines Corp
•
Filing: 1967-05-18
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Granted: 1970-01-13
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Expires: 1987-05-18
Abstract
No abstract record available.
Inventors
- 👤 Fred Barson
- 👤 Vir A Dhaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:37
CPC Classifications
H; H10; H10P; H10P95/00; H10W; H10W74/00; H10W74/40; H10W74/43; Y; Y10; Y10S; Y10S148/00; Y10S148/043; Y10S148/145
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3312881A
Cited
US3389023A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-01-12 | 1973-07-14 | 1974-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-01-12 | 1977-07-14 | 1978-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-01-12 | 1981-07-14 | 1982-01-13 | $7700.00 | Window Closed / Lapsed |