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So, there isn't anything to do to know if this is a refurbished or a new one ? What about people who exchanged their iPhone 5S like me ? What are your serial numbers ?
 
So, there isn't anything to do to know if this is a refurbished or a new one ? What about people who exchanged their iPhone 5S like me ? What are your serial numbers ?

There are multiple factories. Multiple serial number designations for internal part revisions, factory, week. You would need thoussands of samples to even begin decoding.

Relax, enjoy your working device.
 
@Menel: I'd like to enjoy my iPhone 5S but the first iPhone had a 10h30 battery (in usage time) with wifi on and a little of browsing but the "new one" has a 6 hours battery with the same usage...
 
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