US2809556A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contact lens
Assignee: Dr Ritholz & Sons Co
•
Filing: 1952-03-24
•
Granted: 1957-10-15
•
Expires: 1972-03-24
Abstract
No abstract record available.
Inventors
- 👤 Joseph J Hornstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:35
CPC Classifications
G; G02; G02C; G02C7/00; G02C7/02; G02C7/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1921971A
Cited
US2198868A
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US2247628A
Cited
US2438743A
Cited
US2510438A
Cited
US2544246A
Cited
US2653515A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-14 | 1961-04-15 | 1961-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-14 | 1965-04-15 | 1965-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-14 | 1969-04-15 | 1969-10-15 | $7700.00 | Window Closed / Lapsed |