Stolen Iphone
Can apple block a stolen iphone by its serial number? Does the phone serial number embedded on the firmware, can it be changed using a program? I know an IMEI can be replace but the serial number, no idea.
iPhone X
no, apple can't block anything by anything it's not legal for them to track or deactivate equipment sold to customers
carriers can block by IMEI
if you phone get stolen
If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support
