That’s what the instance name (hosted on their domain) provides. I can put an @microsoft.come email in my profile, but it’s meaningless because it’s not verifi

That’s what the instance name (hosted on their domain) provides. I can put an @microsoft.come email in my profile, but it’s meaningless because it’s not verified. But if MS has their own instance, then your handle(?) proves you have an account on that instance. And presumably only employees and company accounts would be allowed to have such user accounts.