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US3401802A
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Assignee: NL Industries Inc
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Filing: 1967-08-08
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Granted: 1968-09-17
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Expires: 1987-08-08
Abstract
No abstract record available.
Inventors
- 👤 James D Fann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:03
CPC Classifications
E; E21; E21B; E21B49/00; E21B49/005; B; B01; B01D; B01D29/00; B01D29/01; B01D29/11; B01D29/114; B01D35/00; B01D35/14; B01D35/147; B01D35/1475; E21B21/00; E21B21/06
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) | 1971-09-17 | 1972-03-18 | 1972-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-09-17 | 1976-03-18 | 1976-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-09-17 | 1980-03-18 | 1980-09-17 | $7700.00 | Window Closed / Lapsed |