US3497639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Simultaneous-call telephone test system
Assignee: Stromberg Carlson Corp
•
Filing: 1966-07-08
•
Granted: 1970-02-24
•
Expires: 1986-07-08
Abstract
No abstract record available.
Inventors
- 👤 Richard M Malinich
- 👤 Donald J Mariotti
- 👤 Theodore M Stump
- 👤 William L Winchell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:37
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/32; H04M3/323
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3239612A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-02-23 | 1973-08-25 | 1974-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-02-23 | 1977-08-25 | 1978-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-02-23 | 1981-08-25 | 1982-02-24 | $7700.00 | Window Closed / Lapsed |