Can I restore without activating my iPhone?

[Da Dude Man]

I'm trying to sell my old iPhone, but I want to make sure it is set up as new iPhone but I can't get to that part because I have to activate it with AT&T first. There's no sim card so I can't activate it. I just don't want any of my stuff on it when I sell it. I updated it to the latest software and that's when this happened. Is it already wiped? Is it good to go like this?

[BrownGem]

If you only updated it and didn't restore it as a new device your content is still on it. Maybe you have a friend with an AT&T sim you could put in it to try and access the phone. Then you could use erase all settings and content feature on the phone.