Under this logic, copyleft is also a use restriction. It bars proprietary use of free software.
Being proprietary is not an attribute of the use. It is a description of the exclusion of other uses than the mentioned. Nothing distinguishes the "proprietary usage" from the "non-prorietary usage" when looking at the actyual useage only. Your ability to *use* is not restricted by copyleft. Your ability to prevent others from using your modification is. So "proprietary use" is not a type of usage, and its restriction is not a use restriction. Regards /L -- Lasse R. Nielsen - atwork@infimum.dk 'Faith without judgement merely degrades the spirit divine'