Plum Analytics is a for-profit company, owned by EBSCO. The company collect metrics for any research output that is available online, including books and book chapters, preprints, reports, dissertations, videos and web pages. Impact metrics fall into 5 main categories: usage, captures, mentions, social media and citations.
Plum X is marketed to universities and research institutions as a way to track researchers' productivity. As well as providing metrics for individual articles, it can provide them for labs, departments or other groups.