US2776793A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ladder construction
Assignee: International Steel Co
•
Filing: 1952-02-01
•
Granted: 1957-01-08
•
Expires: 1972-02-01
Abstract
No abstract record available.
Inventors
- 👤 Karl F Nystrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:53
CPC Classifications
B; B21; B21K; B21K7/00; B61; B61D; B61D23/00; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49616
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US283136A
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US1134087A
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US1157602A
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US1215455A
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US1285520A
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GB175157A
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US1954545A
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US2350875A
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US2306710A
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US2594840A
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US2594516A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-08 | 1960-07-09 | 1961-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-08 | 1964-07-09 | 1965-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-08 | 1968-07-09 | 1969-01-08 | $7700.00 | Window Closed / Lapsed |