I have searched high and low to try and find an answer to my situation, and I truly hope someone can shine some light on this for me.

Divorce decree (NC from 2005) states "so long as the Husband is providing child support for the minor child, the Husband shall be entitled to claim the minor child as an exemption for Federal and State income tax purposes, and the Wife shall NOT claim the minor child as an exemption".

Husband has been claiming child as a dependant on income taxes since 2005.
Husband paid child support until minor child turned 18 (as stipulated in the divorce decree) in August, 2013.

Ex-wife just advised that she is claiming our son on her (2013) tax return. Should I, the Husband not be allowed to claim my son for 2013, as I paid the child support for 8 months out of the year?

Any help, greatly appreciated!