The badge-list you see there is auto-generated. Any tag in which any user has earned enough rep to merit a badge will be in that list. Earn enough rep in the [tag:proliant] tag, and you'll see the badge in there. From the looks of it, you're only [four upvotes short][1] of earning the Bronze tag-badge for that very tag. It'll be there soon!


  [1]: https://serverfault.com/tags/proliant/topusers