Suppose there are two copies of NEXT Silver rezzed, and no other NEXT ice. The runner has Clone Chip, Grimoire, and Grappling Hook installed. The runner encounters one of them, uses Grappling Hook to break one subroutine, and then uses Clone Chip to bring out a Parasite on the other NEXT Silver, killing it immediately.
Is the one subroutine of the ice being encountered broken, or unbroken?
If it is broken, and if Chum applies, would Chum deal damage? The subroutine on NEXT Silver is broken, and Chum would not deal the Runner any damage.