All Microsoft Office installations require software activation. Windows versions will activate from the internal Key Management System (KMS) automatically without any intervention on the users part. On rare occasion, the software fails to activate. In this case, send a helpdesk ticket of assistance in forcing the software activation through.
The Mac version of Office 2011 does not require activation. The activation method for Office 2016 is currently through an Office 365 account. These accounts have been setup for Mac users and being deployed to the Mac users. If we missed you, send a helpdesk request. An automatic activation version of Office 2016 for mac should be available late September 2015.