Interesting:

Originally Posted By Diki
Henni, I’d take a careful look at copyright laws around the world before you start a commercial venture using hit songs.


https://www.facebook.com/groups/sgubackingtracks/posts/1054695052251009/?comment_id=1054702038916977

which states:

Ok, ANYTHING created WITHIN BIAB is NOT subject to copyright as PG music make very clear in the manual. The main reason for the lack of .SGU files is more down to the amazing real track performances, which, again are NOT subject copywrite. You are free to use them on any recording you like and release them with NO requirement to credit either PG Music or the original musician.
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