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US3421141A
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Assignee: Huntec Ltd
•
Filing: 1967-10-16
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Granted: 1969-01-07
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Expires: 1987-10-16
Abstract
No abstract record available.
Inventors
- 👤 Henry J Meyerhoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:31
CPC Classifications
G; G01; G01V; G01V1/00; G01V1/28; G01V1/36; H; H03; H03H; H03H21/00; H03H21/0001; H04; H04B; H04B3/00; H04B3/02; H04B3/20; H04B3/23; Y; Y10; Y10S; Y10S367/00; Y10S367/901
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2966584A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-07 | 1972-07-08 | 1973-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-07 | 1976-07-08 | 1977-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-07 | 1980-07-08 | 1981-01-07 | $7700.00 | Window Closed / Lapsed |