US3527889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Conference communication system
Assignee: U S Holding Co Inc
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Filing: 1967-03-01
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Granted: 1970-09-08
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Expires: 1987-03-01
Abstract
No abstract record available.
Inventors
- 👤 Carl B Nennerfelt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:39
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/42; H04M3/56; H04M2203/00; H04M2203/50; H04M2203/5063
Claims Analysis
Total Claims: 0
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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) | 1973-09-07 | 1974-03-09 | 1974-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-09-07 | 1978-03-09 | 1978-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-09-07 | 1982-03-09 | 1982-09-08 | $7700.00 | Window Closed / Lapsed |