You are here: Popular Formats > Google KML Reader/Writer > Writer Overview and Workbench Parameters > Style Management and Common Styles > Unique Id Values
The style registry assumes that each style id is unique. Style ids are specified by the kml_id format attribute of features with Style and StyleMap feature types. This includes Style elements created as a result of Common Style' references; the resulting Style element has an id that is the same as the value of the kml_common_style format attribute.