It's not fair to reduce the role of Windows to an advertising tool. It's also a spyware.
There are legal resellers, that sell them for about 200-300 USD per license.
There are shady resellers, that sell them very cheaply, but I always suspect they are pirated.
You can't buy something for $100 and sell it for $20. Well, you can, but this is not a sound business model.
It's always amusing for me when people assume they can buy a 'legal' copy/key for $5-10 'somewhere on the net'.
The only way to resell something from a bankrupt company is to buy a retail box versions of software in the first place and LTSC is not available in retail.
> If you acquired the software from a retailer as stand-alone software, you may transfer the software to another device that belongs to you, but not more than one time every 90 days (except due to hardware failure, in which case you may transfer sooner).
It is highly probable that, if anybody cared, you could win such a case in a European court but I'm not aware if anyone bothered to try.
I thought this had recently been ruled in favour of re-sale - but the newest i could find was on Vernor v. Autodesk, which goes the other way...
https://dunnerlaw.com/buyer-beware-the-threat-to-the-first-s...