Can I get these iPhones activated with AT&T?

So I bought 2 iphone 4's and 2 iphone 5s's all of them are SIM card and will be activated with ATT so when I take these to the store what is gonna happen? When I looked up the imei it said not black listed and it said "activated" what's that mean? Also I tested the phones by using my friends SIM card who also has att and they connected just fine.

Yes you can

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