Another source confirming this treatment on the FAFSA (which in my experience, no CSS Profile schools deviate from):
“Money held in a 529 plan, and the plan’s ownership status, comes into play when determining aid eligibility. If the account owner is the student and that student is dependent, or the account owner is the parent of a dependent student, 529 plan funds are treated as a parent’s asset on the FAFSA…If the account owner is an independent student, 529 plan funds are treated as the student’s asset.”
https://smartasset.com/financial-advisor/529-plans-custodial-vs-individual
I addition to the previous “loophole” I described about dependent student-owned 529 being treated as parental assets above, you might have notice a sibling loophole. This article expands on that:
First it states " If the 529 plan of a dependent student is a custodial 529 plan, it is reported as a parent asset on the student’s FAFSA. If the 529 plan of the student’s sibling is a custodial 529 plan, it is not reported as a parent asset on the student’s FAFSA, just on the sibling’s FAFSA.
And then it goes on: " Loophole Involving Custodial 529 Plans of a Sibling
This creates a loophole where 529 plan assets of a sibling are not reported on the FAFSA if the 529 plan is a custodial 529 plan and not a parent-owned 529 plan…
…This loophole may become more important under the new simplified FAFSA for the 2024-25 academic year. A major change in the new FAFSA rules is that families will not receive any benefit from having more than one child in college at the same time…"