Officially the warranty is only valid for the original equipment owner, it doesn’t transfer if they sell it (I have heard of devices being replaced under warranty for the second owner if they have a valid license, but it can’t be guaranteed).
You can sell the device, but often you may find people reluctant to purchase them as they can’t be sure it isn’t claimed, and you can’t give them the serial number until they’ve purchased it (as they could just claim it and stop anyone from using it). If you do sell it they will need a license, so it’s good to let them know that. You should also advise whether it’s a -NA or -WW version as that will determine where it can be used (assuming you’re happy to ship overseas if requested).