If you have never given your ex a signed form 8332, then you may have been allowing your ex to claim dependent status as if the child lived with him. This is not only improper, but it may have deprived you of certain tax benefits, particularly if you pay for childcare so that you can work, or if you qualify for earned income credit. You may want to talk with a tax advisor about amending some of your past tax returns. Of course, this will cause his returns to be examined but if he has been claiming improper dependents, that's his problem.
