Portfolio comparison
Theophilus Van Kannel vs Electrolux Servel Corp
Side-by-side portfolio analysis — patents indexed, year ranges, and activity timeline.
Top Patents1 enriched
US 387571· 1888
How the Revolving Door Was Invented
Activity by Decade
1880s1
Top Patents1 enriched
US 1781541· 1930
How Albert Einstein and Leo Szilard Designed a Silent Refrigerator
Activity by Decade
1930s1
How to use
Bookmark a comparison URL to save it. Format: /compare/companies?a=[slug]&b=[slug]. Also see patent-level comparison.