Inventors' Day

[1] The Inventors' Day (German: Tag der Erfinder) in the German-speaking countries Germany, Austria and Switzerland is celebrated on 9 November, the birthday of the Austrian-born inventor and Hollywood actress Hedy Lamarr whose main invention was the frequency-hopped spread spectrum 1942.

Hungarian Inventors' Day (Magyar Feltalálók Napja) is celebrated on 13 June in memoriam of Albert Szent-Györgyi who registered his national patent about the synthesized Vitamin C in 1941.

[4] Since 1957, Russia has celebrated an Inventors' and Rationalizers' Day (Russian: День изобретателя и рационализатора) annually at the last Saturday of June.

The Thai Cabinet set this date to commemorate the anniversary of His Majesty King Bhumibol Adulyadej’s allocation of a patent for a slow speed surface aerator on 2 February 1993.

Ronald Reagan as President of the United States proclaimed 11 February 1983 as National Inventors' Day, Proclamation 5013 Archived 2014-04-10 at the Wayback Machine, to "...call upon the people of the United States to observe this day with appropriate ceremonies and activities".