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US2977874A Expired / Lapsed US ⏱️ 0.0 years remaining

Operation control arrangement for duplicators

Assignee: Individual
•
Filing: 1958-10-21
•
Granted: 1961-04-04
•
Expires: 1978-10-21
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Abstract

No abstract record available.

Inventors

  • 👤 Ritzerfeld Wilhelm
  • 👤 Ritzerfeld Gerhard

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 08:46
CPC Classifications
B; B41; B41L; B41L39/00

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US2076241A Cited
US2220255A Cited
US2335954A Cited
US2558157A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1964-04-03 1964-10-03 1965-04-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1968-04-03 1968-10-03 1969-04-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1972-04-03 1972-10-03 1973-04-04 $7700.00 Window Closed / Lapsed

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