Portfolio comparison
PPG Industries vs John Harvey Kellogg
Side-by-side portfolio analysis — patents indexed, year ranges, and activity timeline.
Company A
PPG Industries
Patents indexed
1
Year range
1981
Most recent
1981
chemicalenergymanufacturingmaterialsindustrial_process
Top Patents1 enriched
US 4253922· 1981
How a Special Carbon-Fluorine Catalyst Makes Chlorine and Caustic Soda
Activity by Decade
1980s1
Top Patents1 enriched
US 558393· 1896
How John Harvey Kellogg Invented Flaked Breakfast Cereals
Activity by Decade
1890s1
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