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Special rules apply for divorced or separated taxpayers claiming the credit. Generally, only the custodial parent can claim the credit. Also, even if the custodial parent releases or gives the noncustodial parent the right to claim thedependency exemption for the child, the noncustodial parent still can't claim the credit.
Also, you may be able to claim the credit even if your child isn't your dependent so long as all other requirements are met and:
1) You're the custodial parent
2) You had custody of the child for more than half the year
3) You or your ex-spouse provided over half the child's support
Since your ex did not provide over 50% support (he didn't seem to provide anything), it is a good argument that he shouldn't receive the credit. You need to contact you divorce attorney and respond to your ex's motion and your next move should be to ask for back child support as well as support your decision to take the credit and try to get a ruling for you to continue to do so until your ex catches up on support. Contact your attorney ASAP.
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