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US2173904A
Expired / Lapsed
US
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Electrode system of unsymmetrical conductivity
Assignee: Koninklijke Philips NV
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Filing: 1936-03-04
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Granted: 1939-09-26
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Expires: 1956-03-04
Abstract
No abstract record available.
Inventors
- 👤 Holst Gilles
- 👤 Willem Christiaan Van Geel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:11
CPC Classifications
H; H10; H10D; H10D99/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-09-25 | 1943-03-27 | 1943-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-09-25 | 1947-03-27 | 1947-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-09-25 | 1951-03-27 | 1951-09-26 | $7700.00 | Window Closed / Lapsed |