The fm-data-marker element round-trips to DITA as the data element, and allows you to make use of multiple marker types in FrameMaker. When you insert an fm-data-marker, that element saves to DITA as a data element with the @datatype attribute set to “fm:marker” and the @name attribute set to the marker’s type. The marker text is assigned to the @value attribute.

The element definition of fm-data-marker is identical to that of the the data element, except that the object type is a Marker instead of a Container. Also the @class attribute is “topic/data fmx/fm-data-marker.” The plugin handles the conversion from fm-data-marker to data and back; no read/write rules are needed for this element.