The US Patent Office lists Devee J. and Christopher Govrik, of St. Paul, MN, as the inventors. Several sites say the Twist-Off Bottle Cap was invented in 1956, but don't say by whom. The US Patent Office says that was invented by John C. Henning of Fairfield, OH. Other patents are held by different people for variations of it.
patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2 and Sect2=HITOFF and p=1 and u=/netahtml/search-bool.html
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