Flash CS6.
shape.isFloating
Read-only property; if true, the shape is floating above the parent frame’s (or group’s) shape. Also, if true, this type of shape will have it's own matrix, similar to a drawing object.
The following example displays whether a specified shape is floating:
var myShape = fl.getDocumentDOM().getTimeline().layers[0].frames[0].elements[0];
fl.trace("is shape floating? " + myShape.isFloating);