If you filed a joint return, and are still residing with your spouse, both you and your spouse should
sign the form or statement. If you filed a joint return and you now have separate addresses, each of you
should notify us of your new, separate address. Authorized representatives filing a form or written
statement to change an address for a taxpayer must attach a copy of their power of attorney or Form
2848, Power of Attorney and Declaration of Representative. Unauthorized third parties can't change a
taxpayer's address.