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I am the custodial parent. My Divorce decree says that the petitioner (which is me) may claim the minor child unless they do not benefit. I did not work in 2018 as I went back to school for my masters. Thus, I can not benefit. My ex is stating that means they can now claim the child and trying to force me to sign form 8232. My understanding is that I may claim but I am not required to claim if I do not benefit. The respondent is not even referenced. Am I right in thinking that signing the form is optional.and not required since the divorce decree does.not specifically state that the respondent can claim the child if I do not benefit?