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US2688181A
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Assignee: TUBING SEAL CAP Inc
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Filing: 1952-08-04
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Granted: 1954-09-07
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Expires: 1972-08-04
Abstract
No abstract record available.
Inventors
- 👤 Frank W Livermont
- 👤 Harry E Collins
- 👤 William F Gresham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:22
CPC Classifications
B; B21; B21D; B21D26/00; B21D26/02; B21D26/033; B21D26/039; B21D26/047; B21D45/00; B21D45/02; Y; Y10; Y10T; Y10T292/00; Y10T292/82; Y10T428/00; Y10T428/12; Y10T428/12229; Y10T428/12271
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) | 1957-09-06 | 1958-03-08 | 1958-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-09-06 | 1962-03-08 | 1962-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-09-06 | 1966-03-08 | 1966-09-07 | $7700.00 | Window Closed / Lapsed |