Kasimir Bileski (September 14, 1908 - January 19, 2005) was a noted Canadian philatelist and stamp dealer based in Winnipeg, Manitoba, Canada. He is best known for his discovery and promotion of the famous "Seaway Inverted" stamps of 1959.[1][2]
He was also involved in the holding of many of Canada's rare stamps, and wrote widely on philatelic issues.