Patent US3221503A successfully refreshed from Google Patents.
US3221503A
Expired / Lapsed
US
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Method of producing relativelycalm water area
Assignee: Individual
•
Filing: 1961-06-28
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Granted: 1965-12-07
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Expires: 1981-06-28
Abstract
No abstract record available.
Inventors
- 👤 Allen B Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:49
CPC Classifications
E; E02; E02B; E02B1/00; E02B1/003
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
FR358737A
Cited
US843926A
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US1423640A
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US1593863A
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US2325937A
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US2382393A
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US2417519A
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US2967399A
Cited
FR1237407A
Cited
US3103788A
Cited
US3109288A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-12-06 | 1969-06-07 | 1969-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-12-06 | 1973-06-07 | 1973-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-12-06 | 1977-06-07 | 1977-12-07 | $7700.00 | Window Closed / Lapsed |