The conversation between human and AI assistant.
[|Human|] Why is the sport commonly known as "Ultimate Frisbee" legally recognized only as "Ultimate"?
[|AI|] The key reason why the sport "Ultimate Frisbee" is legally known as "Ultimate" comes down to copyright issues. The sports company "Wham-O" trademarked one of their products as the "Ultimate Frisbee" which would require licensing fees for the sport to use this name or risk facing legal action.
[|Human|] 
Why is the sport commonly known as "Ultimate Frisbee" legally recognized only as "Ultimate"?