Surprising that the only mention of intellectual property in the FAQ and the legal terms page is about copyright that the service claims in the outputs, not restrictions on the inputs.
The ToS for this claims that you have to pay for it to use the results commercially, but I couldn't find the pricing for it anywhere or any way to sign up.
Interesting, as the primary use case for this seems to be something along the lines of editing music to fit into video projects.
I plan to implement paid features later with a basic free tier. I am still trying to figure that out. I've updated the terms to be more clear about that!
since there is no login mechanism, I used the anonymous feedback section to request their agreements with BMI and ASCAP for creating liscenced mechanical renditions of copyrighted materials.
This is a good point, I have updated the site to only allow you to view content you submitted and also made it clear that you need to have the rights to the audio to edit it.
Interesting, as the primary use case for this seems to be something along the lines of editing music to fit into video projects.