The first approach is to silently include "watermarks" within 3D models. In this way a print could theoretically be traced back to the legitimate owner. Forensics could perhaps identify the source of the theft. It may not work in every case, but the presence of watermarks carrying unknown details may deter some intellectual property thieves from acting.
The second approach is more complex, we feel. Authentise has created SendShapes, a service for distributing 3D models. They're trying to leverage the difference between a CAD 3D model and a printable STL 3D model.
A CAD model is a manipulatable design, composed of parametric elements that can be modified without affecting the rest of the model. Think "making the wheels bigger" or "changing the thread size on the bolt hole". The CAD model cannot be 3D printed directly and must first be converted into a stream of instructions for the 3D printer to use.
A printable 3D model has been compiled into printer machine code. This is specific to each 3D printing device and is effectively not modifiable as a CAD model might be.
Capturing the data stream between Model and Printer enables all kinds of interesting controls and statistics. Authentise can provide usage statistics for models, “pay per print” and other options.
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