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US3531209A Expired / Lapsed US ⏱️ 0.0 years remaining

Digital printout spectrophotometer

Assignee: Evans Electroselenium Ltd
•
Filing: 1967-09-11
•
Granted: 1970-09-29
•
Expires: 1987-09-11
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Abstract

No abstract record available.

Inventors

  • 👤 Vivian Roy Williamson
  • 👤 Kenneth John Riggs

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:38
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/27; G01N21/01; G01N21/03

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US3364811A Cited
US2972925A Cited
US3263554A Cited
US3142719A Cited
US3377467A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1973-09-28 1974-03-30 1974-09-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1977-09-28 1978-03-30 1978-09-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1981-09-28 1982-03-30 1982-09-29 $7700.00 Window Closed / Lapsed

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