It depends on the agreement between you and the company when you bought them: it would be legal for the company to reimburse you the money you pay for *your* own devices, so you own them; and it would be equally legal for the company to buy these things for you and own them, so that they stay with the company when you leave. If there is something in writing, including emails or text messages, showing what the thinking and agreement was at the time you did this, you should rely on what it says. If there is no clear indicia of who owns the devicies when you leave, then if you take/keep them, the company could try to sue you for them (or their value) and leave it to a judge to decide.