Recently my mother filed her taxes for this, and the previous year but it's unclear of how long we can go back.
The IRS representative officially said due to the statue of limitations we can't file back longer than some years, but they never said how long.
Due to various issues in the past probably ten years, she hasn't filed. However, the representative stated if she owned them money they would have done so for her; which implies that she's probably have had a sum of money due back to her for some time.
So for clarifications how far back can she file? I'm failing to find an official document on this.