Patent US2121202A successfully refreshed from Google Patents.
US2121202A
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Assignee: Individual
•
Filing: 1935-03-19
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Granted: 1938-06-21
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Expires: 1955-03-19
Abstract
No abstract record available.
Inventors
- 👤 Robert J Killgore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:03
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/46; E21B10/56; E21B10/567; E21B10/5676; E21B10/006; E21B10/08; E21B10/12; E21B10/50; E21B10/52; Y; Y10; Y10T; Y10T407/00; Y10T407/19; Y10T407/1906; Y10T407/1952; Y10T407/1956
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) | 1941-06-20 | 1941-12-20 | 1942-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1945-06-20 | 1945-12-20 | 1946-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1949-06-20 | 1949-12-20 | 1950-06-21 | $7700.00 | Window Closed / Lapsed |