Patent US4633209A successfully refreshed from Google Patents.
Patent US2331647A successfully refreshed from Google Patents.
US2331647A
Expired / Lapsed
US
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Retainer
Assignee: AT&T Inc
•
Filing: 1942-11-10
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Granted: 1943-10-12
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Expires: 1962-11-10
Abstract
No abstract record available.
Inventors
- 👤 Elmer E Barkstrom
- 👤 Henry M Larsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:12
CPC Classifications
B; B65; B65H; B65H49/00; B65H49/36; B65H2701/00; B65H2701/30; B65H2701/31; Y; Y10; Y10T; Y10T24/00; Y10T24/46; Y10T24/4604; Y10T24/4605; Y10T24/4609; Y10T24/4621; Y10T24/4627
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) | 1946-10-11 | 1947-04-12 | 1947-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1950-10-11 | 1951-04-12 | 1951-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1954-10-11 | 1955-04-12 | 1955-10-12 | $7700.00 | Window Closed / Lapsed |