When it was discovered last Friday that Verizon’s (VZ) iPhone 5 came unlocked, customers started questioning how long it would be before the carrier locked it back up. After all, Sprint (S) initially sold unlocked iPhone 4S handsets and then locked them back up last year. Verizon has confirmed to The Associated Press that it will not lock the iPhone 5 nano-SIM slot in any future update, however. This is great news for customers who want Verizon’s coverage over CDMA and 4G LTE in the U.S., but also want the freedom to pop in another carrier’s nano-SIM card when roaming internationally. As for why Verizon has decided to pass on this grand gesture to its customers, MacRumors reports that an FCC regulation prevents the carrier from locking any handsets that run the 700 MHz spectrum. In this case, Verizon uses the spectrum for its 4G LTE network.