Head to your Resource Center, and select the Category of your choice and the Resource you want to manage.

Scroll to the bottom of your page, and you'll see all partners that have been assigned to the resource (via resource center categories)

For more information on how to set up your Resource Center, check out this article.

Click View History to see which users at the partner company have viewed the Resource.

Once a Partner has viewed the Resource, the history will update to reflect this.

A partner's view will inform them of how many resources they have not viewed in a category and will update as they continue viewing.