What should an iphone do with no sim card?

I have this extra iphone 4s that I have never used before. In the top left corner it says "searching" even though it has no sim card in. Is this normal?

Its possible that it could be a CDMA iPhone 4s meaning it wouldn't need a SIM & would work on a CDMA carrier like Verizon & probably not activated at that point.

May as well sell it.