3D models saved in SAT format (ACIS models) can be converted to a multitude of other 3D model formats, including ISO STEP product data file. Such sat to stp conversion most likely works only for the meshes thought, but plenty of software should be capable of this.
Open SAT file Open STP fileA CAD viewer program with conversion capabilities
A set of 3D modeling tools
A CAD conversion software
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A design software for optical engineers