In the past IP reputation & segmenting types of email to different IP’s was the obvious delivery tactic for many email senders.  But now the combination of domain reputation and engagement is increasingly making deliverability quite a challenge for some senders.
We have had many people contact us to help remove non-engaged subscribers.  We even had some internal tools to help do this on-demand.  We recently took a little time to add the capability into everyone’s account so you can manage your engagement and clean up any subscribers that have not engaged in a specific time period.

When you click “View Cleanup Options” you have the option to either remove all subscribers who have not engaged ever or anyone who have not engaged within a specific time period.
You can find this new page by going to Lists. Next to each list there is a down arrow. Clicking the down arrow will display a list of options. Click “Engagement Management” to navigate to this feature.