Portfolio comparison
John L. Mason vs Marvin C. Stone
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 375962· 1888
How the Modern Paper Drinking Straw Was Invented
Activity by Decade
1880s1
How to use
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