My last eBay sale:
$59.98 - 7.50 ebay - 2.04 paypal =$50.44
Less $5 shipping = $45.44
Factoring out shipping costs, then that means they took 17.4% of the spoils.
This is why I don't sell there often.
They also have tons of federal grants, with many from the defense department. Though with that said I am sure patent ownership is well documented in their contracts.
I got frustrated with mine and pitched it. I imagine the kids will just not play with them. Especially kids from the UK who would rather be given Macbook's.