Antimalware Engine 1.1.12400.0 was released to customers on 16 Dec 2015
Antimalware Engine 1.1.12400.0 was released to all Windows Defender, Microsoft Security Essentials, Forefront Endpoint Protection, Windows Intune Endpoint Protection, and System Center Endpoint Protection customers on 16 Dec 2015. Signature package 1.213.0.0 is the first that contains this engine.