I have a question about Leblanc (Warning: this does not refer to balance at all)

Okay, so, in s Q (Shatter Orb), it says

"Leblanc projects an orb at her target, dealing magic damage. When shatter orb is empowered by sigil of malice, the spell bounces to the nearest ready sigil of malice. (Bounces deal 80% damage to minions)"

When it says, "Bounces deal 80% damage to minions" is it saying that the overall damage is reduced to 80%, or only the spell itselves damage does 80%, and then the passive will do normal damage?

If you don't know the answer (or do and just don't feel like telling it) then please just don't comment.