3D printing has revolutionized the way we create custom tools, replacement parts, and everyday gadgets.
But alongside its benefits, the technology has also given rise to troubling uses.
One of the most serious is the rise of so-called “ghost guns”—untraceable firearms made with 3D printers.
Such weapons have already been linked to violent crimes, including the late 2024 killing of UnitedHealthcare CEO Brian Thompson.
Researchers at Washington University in St. Louis are now working on a way to prevent 3D-printed items from being completely anonymous.
Led by Netanel Raviv, an assistant professor of computer science and engineering, the team has developed a method to embed unique, traceable “fingerprints” directly into 3D-printed objects.
These fingerprints remain intact even if the object is broken into pieces, making it possible for forensic investigators to uncover valuable details such as the identity of the printer, the time of production, and even the location where the object was made.
The research will be presented at the USENIX Security Symposium in Seattle this August, and the findings are also available on the arXiv preprint server.
The basic idea is simple but powerful: just as human fingerprints are unique to each person, these embedded identifiers are unique to each printed object.
Current approaches to fingerprinting in 3D printing involve embedding data such as timestamps, printer IDs, or geolocation information into an item during the printing process. However, most of these techniques fail if someone tampers with or breaks the printed piece. Raviv and his team wanted to solve that problem.
The group developed mathematical techniques that allow information to be embedded in a robust, break-resistant way.
They call their framework Secure Information Embedding and Extraction, or SIDE. SIDE ensures that even if an adversary tries to tamper with an item—or smashes it into pieces—the embedded data can still be recovered. The approach is “loss-tolerant,” meaning it doesn’t rely on the object being intact in order for investigators to pull out the hidden fingerprint.
SIDE also includes security mechanisms that enforce the use of these embedded codes by 3D printers themselves. In practice, this means printers could be designed to automatically insert the fingerprint data into every object they produce, leaving behind a trail that is invisible to the eye but accessible to forensic analysis.
This new system builds on research Raviv and his student team presented in 2024 at the IEEE International Symposium on Information Theory. In that earlier work, the researchers focused on creating a mathematical framework that could recover original information bits even from fragments of objects that had been deliberately tampered with. The latest study takes that foundation and combines it with added security features, pushing the idea closer to real-world applications.
“This work opens up new venues for protecting the public from the harmful aspects of 3D printing via a combination of mathematical contributions and new security mechanisms,” Raviv explained. He also acknowledged that SIDE has limitations.
Extremely skilled adversaries with deep expertise in 3D printing may still find ways around the system. But, he added, the technique “significantly raises the level of sophistication, prior knowledge, and expertise required from the adversary to remain undetected after committing the crime.”
In other words, SIDE doesn’t make 3D printing immune to misuse, but it does make criminal uses far riskier. By embedding hidden but durable fingerprints into every printed item, this technology could help tip the balance—allowing society to enjoy the benefits of 3D printing while limiting its dangers.
