Portfolio comparison
Central Investment Corp vs William F. Semple
Side-by-side portfolio analysis — patents indexed, year ranges, and activity timeline.
Company A
Central Investment Corp
Patents indexed
1
Year range
1973
Most recent
1973
consumer_electronicsmechanical
Top Patents1 enriched
US 3735375· 1973
How Vacuum Tubes Detect Tiny Changes in High-Resistance Sensors
Activity by Decade
1970s1
Top Patents1 enriched
US 98304· 1869
William Semple's 1869 Patent for Improved Chewing Gum
Activity by Decade
1860s1
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