AutoCAD Map 3D supports SDTS
(Spatial Data Transfer Standard).
SDTS is an import-only format. You cannot export to this format.
When you select an SDTS
catalogue file, AutoCAD Map 3D imports objects and attributes from the
dataset specified in the catalogue file. Typically, a dataset is
a group of .ddf files
with the same filename prefix.
AutoCAD Map 3D imports only
one record per object. If an object has multiple records attached,
only one of the records will be imported.
SDTS has no import driver