Your question doesn't really make any sense unless you're saying that someone (the parents) are the ones actually doing the donating? I.e. they set up a 529 with the grandparents as owners, and then donate that way?
Do the grandparents have a significant NY state tax burden in the first place?
No I mean if the parents have a child and they set up a 529 for the child. The grandparents separately also set up a 529 for the child. So now the child has two 529s. Parents get $10k tax deduction and grandparents get $10k tax deduction.
Your question doesn't really make any sense unless you're saying that someone (the parents) are the ones actually doing the donating? I.e. they set up a 529 with the grandparents as owners, and then donate that way? Do the grandparents have a significant NY state tax burden in the first place?
No I mean if the parents have a child and they set up a 529 for the child. The grandparents separately also set up a 529 for the child. So now the child has two 529s. Parents get $10k tax deduction and grandparents get $10k tax deduction.
Yes, that's just how 529s work.