Dependent and EIC regulations

What is the name of your state? Virginia
I have been divorced for 4 years now. I have been claiming my son as a dependent and for EIC. I have
already filed my taxes and recieved a refund. My exhusband has sent a letter to me from his attorney claiming he has the right to claim our son this year. My son lives with me and has only visitation with his father. Has anything changed in the tax laws reguarding the EIC regulations? Nothing has changed for the past 3 years reguarding my son's address with me.

Since you were married, the dependency exemption goes to the custodial parent (you) unless the divorce/custody decree says that he gets to claim the boy. Dig out your divorce papers. It may be that he gets to claim the boy on alternate years, or if his support is paid in full.