Portfolio comparison
Phillips Screw Co vs Hymen L. Lipman
Side-by-side portfolio analysis — patents indexed, year ranges, and activity timeline.
Company A
Phillips Screw Co
Patents indexed
1
Year range
1936
Most recent
1936
mechanicalautomotiveconsumer_electronics
Top Patents1 enriched
US 2046343· 1936
The Invention of the Phillips Head Screw
Activity by Decade
1930s1
Top Patents1 enriched
US 19783· 1858
How the Pencil and Eraser Became One Tool
Activity by Decade
1850s1
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