I would like to know if and how to amend my 2004 taxes. My ex and his wife claimed my son that lived with me up until at least July of that year then moved in with them. I didn't give permission and he didn't ask. I would like to see how to go about this and if it is worth the effort.
I thought that there was nothing I could do about it at the time but hear that he was in the wrong. Please let me know what forms I need to fill out if this is possible

Thank you
devsnavymom

For 2004 even if you were the one who should have claimed your son, you will not get any tax refund now, as the return for refund must be filed within 3 years of regular due date.

As regards claiming exemption for your son, only the parent who had custody for longer duration can claim the child. Read: Your U.S. Tax Return: Child of separated or divorced parents (http://taxipay.blogspot.com/2008/03/child-of-separated-or-divorced-parents.html)