A method is provided for degrading 3D information such as a 3D image file from its original form so that that the subject matter of the 3D image is altered in a way which prevents one from reverse engineering or manufacturing the subject matter of the 3D image while the degraded image is still identifiable or recognizable as that of the original 3D image. The degrading method selectively alters dimensions or relationships between portions or parts of the 3D image from their original form while maintaining the integrity and recognizablility of the image as that of which was in the original 3D image. The present method can be applied to both original CAD files as well as reduced or lightweight files produced from an original CAD file.