US4457490B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
High temperature valve and seat therefor
Assignee: Keystone International Holdings Corp
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Filing: 1982-02-01
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Granted: 1987-01-06
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Expires: 2002-02-01
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:21
CPC Classifications
F; F16; F16K; F16K1/00; F16K1/16; F16K1/18; F16K1/22; F16K1/226; F16K1/2263
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) | 1990-01-05 | 1990-07-07 | 1991-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-05 | 1994-07-07 | 1995-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-05 | 1998-07-07 | 1999-01-06 | $7700.00 | Window Closed / Lapsed |