Patent GB623992A successfully refreshed from Google Patents.
US2619548A
Expired / Lapsed
US
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Electronic switching apparatus for telephone systems
Assignee: International Standard Electric Corp
•
Filing: 1948-05-15
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Granted: 1952-11-25
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Expires: 1968-05-15
Abstract
No abstract record available.
Inventors
- 👤 Lesti Arnold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:13
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04; H03; H03K; H03K17/00; H03K17/51; H03K17/74; H03K19/00; H03K19/02; H03K19/12
Claims Analysis
Total Claims: 0
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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) | 1955-11-25 | 1956-05-26 | 1956-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-11-25 | 1960-05-26 | 1960-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-11-25 | 1964-05-26 | 1964-11-25 | $7700.00 | Window Closed / Lapsed |