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He would claim himself if he provided more support than the parent did.
For his parent to claim him as a QUALIFYING CHILD they would need to be able to answer "yes" to all of the following questions.
Maybe they claimed him as a QUALIFYING RELATIVE because of his age, if so they were not allowed if he earned $4000 or more.
After you go over the above with him, if the parent could not claim him then tell him to mail in his return claiming himself.
Let me know if you need me to clarify
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