Export > Include > Geometry > 
TurboSmooth
 
 
 

Use TurboSmooth to export the source mesh (non-tessellated version) and the TurboSmooth attributes, for objects with an active TurboSmooth modifier applied.

If you disable this option, the tessellated version of the mesh is exported. To export the source mesh, turn off the TurboSmooth modifier in 3ds Max, and export.