Windows 10 available at a discounted price of $20.
Windows 10 available at a discounted price of $20.
When something is not sold buy authorized party, its grey market. You can't argue with that, its definition of the word. MS do have records of all keys. They do know if it came from volume pack, corporation license bunch or OEM licensed to some manufacturer. Thats how they are able to blacklist keys found to be resold against ToS of original purpose. They don't do it in masses as, like it or not, they like to gain market share and abilities it brings. I don't (often) take stance whether someone should buy grey market key or not. But calling keys legit/illegal or some marketplace legit for getting keys or not is different. That should always be mentioned when user asks if something is authorized place to buy or not.
It's not a major concern. Keys are generated through algorithms and software, so there isn't a permanent record of each one. They evolve continuously. What matters is whether they meet certain requirements when activated, which is primarily controlled by the software. If they fail to match, it indicates an issue—especially with some OEM keys that might already be active on a system. Most grey market keys aren't marked as illegitimate, making it simple to verify by trying to activate them. When you attempt activation and it works, it confirms legitimacy without any warnings. There are exceptions, though, where systems flag certain keys, but these cases are limited and affect only a few types of keys.