The purpose of this article is to provide information about a behavior present in the BlueCoat DLP (now Symantec DLP).
Blue Coat DLP (not to be mistaken with Symantec DLP), as of the date of this article (4/20/2017), does not have a feature to automatically delete retained alert records. Currently, they need to be manually deleted periodically to save disk space. However, Digital Guardian (Blue Coat DLP vendor) has an enhancement request on record for that feature. No date has been set for its implementation at this time.