As soon as you think it's stolen you need to call the police on 101 or take the item to your local police station. They’ll try to return it to its original owner. You shouldn’t keep the item or return it to the seller yourself - this might be considered ‘handling stolen goods’, which is illegal.
so sega can keep the money and send cops after the buyer
I never said, or implied, that. All I said is that Nintendo retains ownership of dev kits it provides to developers. Nintendo would usually have the right to have their property returned. I'm sure there will be jurisdictional differences, but generally the buyer would then turn to the seller to recover their costs.
The guy purchased it fair and share, legally. It is his.
Technically, it's not. As the summary mentions, Nintendo retains ownership of their dev kits. As such, Sega would not be authorized to sell the dev kits. From a legal standpoint, I'm not sure if that would provide grounds for Sega to demand the property back. From what little I can easily gather, I don't think Sega has any right to demand the reversal of sale, only request it. Nintendo, however, would still have the right to reclaim the property.
False. Exclusivity contracts are explicitly illegal when combined with significant market power.
The part you overlook is that it has to have gone through court to get to that point. Like now. It's illegal for them, because of all this.
Exclusivity contracts outside of someone's ecosystem which limits someone else's business to business transactions is by very definition an antitrust violation.
Most exclusivity contracts are legal. It generally only becomes illegal in specific cases like this, where the courts determine it should be.
If entropy is increasing, where is it coming from?