http://blogs.technet.com/b/windowshpc/archive/2010/03/26/activation-filter-new-options-in-beta-2.aspxActivation Filters are used to provide the administrator of a Windows HPC cluster with a mechanism to verify and modify jobs before they are run. For example, a Windows HPC Server 2008 Activation Filter receives the job xml which might contain licenseen-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)