Soft Maximum - best free downloads
dxb

Vextractor
... support; - Output format for vector information: DXF, DXB, WMF, EMF, ArcView Shapefiles, MapInfo MID/MIF, ASCII XYZ, Scalable Vector ...

Alteros 3D
... 3dm, 3dmf, 3ds, asc, ase, c4d, cob, dwg (limited support), dxb, dxf, geo, iv, lif, lvs, lw, lwo, max (limited support), md2, md3, mdl, ...

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