I believe an easier system is being worked on, which should be included in the fleet management. It’s not really an easy problem to solve, since you can’t just allow people to reclaim devices themselves. It would get really annoying when you found out someone from across the globe has claimed your Core.
So yes, for now, this is the best option. Alternatives may be provided in the (hopefully not so distant) future.
If you’ve mailed the above mentioned address, that will surely be taken care of.
As far as fleet management goes, there’s not a lot to tell yet. It’s a system being designed to be able to more easily interact with large groups of devices. You can read a bit about it over here.
If you do remember the user who owns the core, you can transfer ownership using the particle command line interface.
First log in as the current core owner: particle setup
Then release the core: particle device remove 12345678923456789
The log in as the new owner: particle setup
Claim the core: particle device add 12345678923456789
I’m including this here because I found this topic through Google and I thought that contacting support was the ONLY way to transfer ownership of a core.
I did contact Particle and they do, indeed, have a system for getting back LOST devices. When I say LOST, I mean you let someone play with some of your devices and they registered them under a quick temporary email and no one can remember the owner.
Dum but it has happened.
The procedure is long and complicated and I urge you to keep track of all your devices and how they are registered at Particle.
To get started retrieving a lost core:
Drop an email to hello@spark.io with your core id and make reference to this thread.