The DRM_Flags property is used with DRM version 1 content only to specify the rights that will be contained in the local license. Rights are specified with values defined by the WMT_RIGHTS enumeration type. More than one value can be selected by combining them with the bitwise OR operator.
When accessing the IWMHeaderInfo3 interface of the writer object, you can add or change this value. In other objects (metadata editor, reader, and synchronous reader), this value is read-only. Use IWMHeaderInfo::SetAttribute to set this property when creating DRM version 1 content.
Build date: 11/16/2013