What shall I report to SIAE when I apply for the stamp? Follow
You need to declare that you're registered with Soundreef.
If SIAE registrations aren't involved (directly or indirectly) in the production for which you're applying the stamp for, you can apply for a reduced payment.
To get it, you just have to make a self-declaration in which you report:
that you aren't enrolled with SIAE and that none of the tracks are registered with the SIAE.