US2612544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polarized electromagnetic device
Assignee: Sigma Instruments Inc
•
Filing: 1948-09-16
•
Granted: 1952-09-30
•
Expires: 1968-09-16
Abstract
No abstract record available.
Inventors
- 👤 Richard T Fisher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:05
CPC Classifications
H; H01; H01H; H01H51/00; H01H51/22; H01H51/2272; H01H51/2281
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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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) | 1955-09-30 | 1956-03-31 | 1956-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-09-30 | 1960-03-31 | 1960-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-09-30 | 1964-03-31 | 1964-09-30 | $7700.00 | Window Closed / Lapsed |