@falcon I'm just saying there's no protocol level way to know domain registration period or transfer of ownership. On top of that, I tend to view the fact that transfer of ownership is possible as a bug. It breaks trust of people using the domain name and, even ignoring certificate issues, can cause a user's browser to disclose secrets to a new party they don't trust. I deem the new owner more of a threat than the old owner still having an unexpired certificate.