for Instruments I would say content should be creative commons for classes, ugens etc. it should be ...?
only for documentation, I think. SC-code is covered by GPL for redistribution of a program: James McCartney writes: http://www.create.ucsb.edu/pipermail/sc-users/2005-September/020784.html"If you distribute an SC program, it is useless without the SC app to run it, so the combination is a derived work and source for the SC patch must be provided."
If you make music with SC and distribute that, then you can keep your program private since you aren't distributing the program."
So a GPL-compatible licence should be added (to cover the use in concerts, albums, films etc.) here I think cc is the right way; the same applies to tutorials and papers, but should be optional in order not to interfere with other publishers agreements.
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