Each carrier has it's own agreement with Apple. It specifies how many iPhones each carrier must sell by a certain point.Is it their fault, or is it something in Sprint's agreement with Apple? China has a version of the iPhone with the TD-LTE bands but not the CDMA radio. Europe, which doesn't even use CDMA, gets the "Sprint" version that has all the LTE bands and the CDMA radio activated. There's no logical reason why the US wouldn't have gotten that version (since it would be one less SKU to worry about) apart from something in Sprint's agreement with Apple. Why else would AT&T, Verizon, AND T-Mobile not want an iPhone capable of supporting the extra TD-LTE bands? The phones already support lots of other bands that those carriers don't use and don't plan on using.
Sprint entered this agreement in 2011. Initially they decided (with the iPhone 4s) that new phones would be unlocked. Shortly after that they rescinded their decision and the phones have been locked domestically ever since.
I do not know what prompted that, but my educated guess is that they discovered people were buying the Sprint iPhone, discovering that the network sucked in their area and then leaving. Since subsidies were still the thing back then, Sprint was still on the hook for the full price of the iPhone.
So, they made it difficult for the customer to leave and use the phone on any other network other than Sprint, thus keeping at least some of their profits.
Sprint's agreement with Apple bars Apple from entering an IMEI in the unlock database for domestic use. Apple can only insert the IMEI when requested by the carrier. Sprint could, but will NOT make the request for domestic use.
Simple as that.
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Sprint''s agreement with Apple prevents Apple from submitting any IMEIs for domestic use to the unlock database. Only Sprint can request that and they refuse.Is it their fault, or is it something in Sprint's agreement with Apple? China has a version of the iPhone with the TD-LTE bands but not the CDMA radio. Europe, which doesn't even use CDMA, gets the "Sprint" version that has all the LTE bands and the CDMA radio activated. There's no logical reason why the US wouldn't have gotten that version (since it would be one less SKU to worry about) apart from something in Sprint's agreement with Apple. Why else would AT&T, Verizon, AND T-Mobile not want an iPhone capable of supporting the extra TD-LTE bands? The phones already support lots of other bands that those carriers don't use and don't plan on using.
Additionally, the iPhone 4s and 5 are paired to their SIM cards, per Sprint's request of Apple. No service without the paired SIM. The iPhone 4 (Sprint) has no SIM and is locked to Sprint's network.
The 5c, 5s, 6 and 6+ have a different SIM. That SIM can be swapped between models, but since Sprint will not submit any IMEIs to the domestic unlock database, the iPhone is still locked to Sprint.
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Sorry for the double quote, but something weird is going on while posting and I can't edit the dang post.