US2495191A
Expired / Lapsed
US
⏱️ 0.0 years remaining
String-of-exchanges telephone system
Assignee: Kellogg Switchboard and Supply Co
•
Filing: 1946-08-02
•
Granted: 1950-01-17
•
Expires: 1966-08-02
Abstract
No abstract record available.
Inventors
- 👤 Bert A Wallace
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:03
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0016
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1953-01-16 | 1953-07-18 | 1954-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-01-16 | 1957-07-18 | 1958-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-01-16 | 1961-07-18 | 1962-01-17 | $7700.00 | Window Closed / Lapsed |