US3421956A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of etching sic
Assignee: International Business Machines Corp
•
Filing: 1965-03-03
•
Granted: 1969-01-14
•
Expires: 1985-03-03
Abstract
No abstract record available.
Inventors
- 👤 Ekkehard Ebert
- 👤 Werner Spielmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:39
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/53; C04B41/5338; C04B41/5361; H; H10; H10P; H10P50/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-14 | 1972-07-15 | 1973-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-14 | 1976-07-15 | 1977-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-14 | 1980-07-15 | 1981-01-14 | $7700.00 | Window Closed / Lapsed |