DB3 File produced by Deduplication

I am using ABR 11.5 with Universal Restore and Deduplication. The deduplication feature saves us a lot of free space and less backup time in our server.

I've noticed that it produce a database file (.DB3) and that file keeps on growing. My questions are can I delete that file and will it affect the backup archive? What happens when I deleted that file? I've attached a sample file.

Your expert answers is highly appreciated.

Thank you so much