How did they have access to those internal IP scores?
When I was doing DMARC stuff professionally, plenty of big names were willing to send DMARC reports our way. Microsoft was the only company to give us full text.
Well, you can (and should!) set up your DMARC preferences through your DNS records and enable a mailbox to receive those reports, which you can then use to verify if you have any/some problems with particular providers. This is totally free and standard.
But the score I am speaking of was something different: it was the reputation assigned by Microsoft (i.e., something internal) to the IPs from which we sent e-mails. This score was used to determine how many e-mails sent from those IPs would pass/fail MSFT's filters. And to have access to the score and improve it, we had to pay a 3rd. party :).
in outlook's admin console, there are a few tools related to antispam, including a way to view stats about why or why not a specific email got sent to spam. IIRC it exposes the sender's reputation score among other things.
But the score I am speaking of was something different: it was the reputation assigned by Microsoft (i.e., something internal) to the IPs from which we sent e-mails. This score was used to determine how many e-mails sent from those IPs would pass/fail MSFT's filters. And to have access to the score and improve it, we had to pay a 3rd. party :).