Portfolio comparison
John L. Mason vs William Stanley, Jr.
Side-by-side portfolio analysis — patents indexed, year ranges, and activity timeline.
Top Patents1 enriched
US 22186· 1858
John Mason's 1858 Patent for the Mason Jar Lid
Activity by Decade
1850s1
Top Patents1 enriched
US 349611· 1886
William Stanley Jr.'s Early Alternating Current Transformer System
Activity by Decade
1880s1
How to use
Bookmark a comparison URL to save it. Format: /compare/companies?a=[slug]&b=[slug]. Also see patent-level comparison.