By what means did you become the owner, in this hypothetical situation? Purchase? Gift? Some other arrangement?

I'm not sure. I had a few possibilities typed out (government auctions, for example) to try and make it really obvious that the ownership was valid, but I figured I could just say "I can prove I own it". But now I'm realizing I left that out of the question.

For instance, if it was understood between you and the previous owner that you only wanted the device for target practice, a court might find that unlocking the device was not a term of the contract agreed between you, and that the previous owner has no obligation to unlock it.

I guess it's possible the offending owner might have sold it to someone under terms where they agreed that it would not be unlocked, and then it could have been sold on without that understanding, meaning the person really to blame for the situation was whoever first passed it off as not being encumbered.

On the other hand, if it was a gift from the previous owner, then I'm quite sure there is no such obligation. Unlocking it for you would be a separate gift that they may or may not decide to give you.

Well, if it was sold to you under the understanding that it would be unlocked, then you can recover from the person who sold it to you, as they breached your contract (whether deliberately or not). You don't have to chase back the chain of responsibility. They, in turn, can go and try to recover from whoever sold it to them, and so on.

But all that said, you do still have to clarify how you acquired ownership, so that we can try to understand whether that transfer was accompanied by an obligation to unlock. It's not enough just to know that you own it. Again, it depends on surrounding facts.

Taking an extreme case - if you throw the phone in the trash can, its ownership passes to someone else - maybe the local municipality, maybe the trash hauling company, depending on local law. But it would be absurd to expect that the trash company could come and legally compel you to unlock it.

Further reading regarding the trash example: When is taking property left on the public street curb a crime?

Another extreme example: a computer is owned by Alice, and as she dies, is inherited by Bob. A lot of the software licenses on the computer will not become Bob's property under the contracts signed, such as Alice's WOW account, or her steam library - nothing ever would legally make you the owner of those based on the contract language.

My understanding is that phones are locked not by the manufacturer, but by the service provider, and only for the period that the phone is being financed by them. (like a bank will hold title to a car, preventing it's sale until the loan is paid in full) If the phone was paid off by the previous owner then the contract terms have been fulfilled. So I'm not understanding how the previous owner even factors into this. What action do you expect them to perform to unlock it? Will the service provider not do this since they can verify that the phone is paid off and account is no longer active?

Because who would sell a phone, not replace it, yet continue paying to keep the account open?!

@MichaelHall this doesn't have to be about service provider. For example, Apple provides a guideline for the owner before selling their devices: What to do before you sell, give away, or trade in your iPhone or iPad. Otherwise, the new owner will be locked out and cannot use the device.

@AndrewT. I understand that they can be locked, I'm wondering why they would be locked if the device is fully paid off.

@MichaelHall the hypothetical posits a device "that can be locked to the current owner's account with the manufacturer" — that is what this question asks about. If the previous owner does nothing, the new owner cannot use the device as they expected. Just accept the hypothetical facts.

@Jen, but if a hypothetical situation is based on a misunderstanding shouldn't we attempt to clear up the misunderstanding in order that any answer will reflect reality and provide useful information? Because the short answer is yes, you can always file a lawsuit, but there may be a more practical solution by working with the service provider.

We are not solving peoples' real life problems on this site; we are answering how the law applies to the hypothetical facts. A hypothetical may very well have been intentionally constructed to not conform to the typical circumstance, for the purpose of teasing out a detail of the law. And if a "more practical solution" is non-legal, they should ask on another site. Of course an answer can allude to the fact that the hypothetical is not realistic in the course of answering the legal question asked.

Not everyone is here for a dry, purely academic and strictly hypothetical legal analysis. Some posters disguise it better than others, and we play dumb, but despite "solving real world problems" NOT being the purpose, let's face it... a solid majority of people posting here do so because they are facing some situation in their lives they want a legal answer to. (which is completely different from advice) "Of course an answer can allude to the fact that the hypothetical is not realistic..." So too could a comment clarify the issue enough to ensure a good answer. xyproblem.info

And: en.wikipedia.org/wiki/XY_problem