Why did I have to fill out a Form 8453-OL for the IRS and mail it in?

I filed my taxes a little over a week ago using an online tax preparation site (it's been around a long time) and I was filing jointly with my husband, it's our first time filing together, and our return was accepted by the IRS but we were instructed to fill out a Form 8453-OL and send it to the IRS office in Austin. It was basically just a signature page type thing. I am wondering why we would be requested to do that, I have never had that happen before and I have been filing taxes for a while.

Public Comments

Form 8453-OL is used to authenticate your electronic filing. when you filed a joint return for the first time, your status changed from previous filings. The IRS wants the signatures of both filers verifying that your electronic filing is valid.
It's not just b/c you're filing joint for the first time---its an authentication tool for the IRS. They want to either see exactly what your return was the year before or some signatures to validate your return. I HAD our refund amount ready to be plugged into Turbo Tax this year, but must have pushed a wrong button, so we had to sign and mail in an OL form. Its really not a big deal--all they do it get the signed OL and plug in the numbers. Send the OL ASAP as soon as your return is accepted to get your refund ASAP.
IRS need Form 8453 to verify your signature they have on file to make sure it is you and not someone trying to file a return using your info