To create the AI model, the team fed it 9,192 photographs of parts. These parts were printed on 21 machines, which were collectively built by six brands and with four different fabrication processes. The team then gave the AI an image of a square millimeter of a printed part, and it managed to pin the print to the machine with 98% accuracy.

I wonder what the accuracy is like with a lot more machines, all of the same brand, model, and fabrication process.

Even 98% accuracy is not very good if we start talking about using this for evidence against someone in court.