New
#11
Basically your rolling the dice. Some sellers are selling TechNet and or MSDN keys. I was a Windows Insider MVP, one of the perks of that is a free MSDN subscription. Its now called a My Visual Studio subscription. Mine is an Enterprise NFR < Not For Resale. And they stress the not for resale aspect. I assume if I was caught reselling my keys they would "all" be immediately blacklisted. If these people only ever sold "a" key to "a" individual it would likely be a usable key. They get greedy and sell the same key multiple times and eventually Microsoft detects the miss use and blacklists the key. They likely don't really care if they get canceled on e-bay. They have no moral code.
Or its somebody that was fired that's reselling any company keys they made note or etc.