The taxpayers received Form 1095-A showing Monthly Advance payment of premium tax credit. There is an adult child (25 years old) on that policy, and she must file her independent return.

Do I have to allocate policy amounts between the taxpayers and that child, or can taxpayers/parents choose to claim 100% of the policy amounts on their return?

If I have to allocate percentage of policy amounts to taxpayers and that child, how do I determine that ratio?