US1871984A
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Assignee: HOFFMAN SPECIALTY Co
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Filing: 1928-06-25
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Granted: 1932-08-16
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Expires: 1948-06-25
Abstract
No abstract record available.
Inventors
- 👤 George D Hoffman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:56
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/02; Y; Y10; Y10T; Y10T137/00; Y10T137/2931; Y10T137/3003; Y10T137/3084; Y10T137/3087; Y10T137/4238; Y10T137/4245; Y10T137/4273; Y10T137/7722; Y10T137/7837; Y10T137/7904; Y10T137/7908; Y10T137/7909; Y10T137/7913; Y10T137/7914
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) | 1935-08-16 | 1936-02-15 | 1936-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-08-16 | 1940-02-15 | 1940-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-08-16 | 1944-02-15 | 1944-08-16 | $7700.00 | Window Closed / Lapsed |