Portfolio comparison
John L. Mason vs John Harvey Kellogg
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 558393· 1896
How John Harvey Kellogg Invented Flaked Breakfast Cereals
Activity by Decade
1890s1
How to use
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