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US2820904A Expired / Lapsed US ⏱️ 0.0 years remaining

Crystal holder

Assignee: US Philips Corp
•
Filing: 1952-10-25
•
Granted: 1958-01-21
•
Expires: 1972-10-25
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Abstract

No abstract record available.

Inventors

  • 👤 Lowitzsch Kurt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 10:33
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/05; H03H9/0504

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US2174809A Cited
US2213306A Cited
US2445132A Cited
US2432913A Cited
US2585916A Cited
US2452045A Cited
US2500926A Cited
US2573056A Cited
US2533747A Cited
US2581219A Cited
US2602899A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-01-20 1961-07-22 1962-01-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-01-20 1965-07-22 1966-01-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-01-20 1969-07-22 1970-01-21 $7700.00 Window Closed / Lapsed

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