The patent holder can demand payment for the right to its use.

VOA: special.2010.03.23

The idea of putting wheels on suitcases goes back only to 1972 and it was Bernard Sadow who invented-- this is amazing, right--the wheeled suitcase and he got a patent on it.

在行李箱上加轮子的想法,可以追溯到1972年2,是伯纳德？沙度发明的-,这很神奇，对吧,并且他凭此获得了专利。

耶鲁公开课 - 金融市场课程节选