// HACKER NEWS — CYBERSECURITY
An ongoing 3D-printer AGPL violation
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At FOSSY 2026, several people from the
Software Freedom Conservancy (SFC),
which organizes the conference, gave a presentation about an ongoing
violation of the Affero General Public
License version 3 (AGPLv3). Bradley Kühn, Karen Sandler, and Denver
Gingerich spoke about different aspects of the violation, which is in
regard to 3D-printer software from Bambu Lab, and what is being
done to try to provide users with alternatives. One aspect that is
particularly interesting is that the circumvention that the company is
employing is precisely what the AGPL was written to prevent.
Kühn began the session by noting that he has been an activist in the free
and open-source software (FOSS) communities for over 30 years and that "this
moment in history [...] has more activism opportunities than I have seen in
my career". In the past, he and his colleagues have been triaging
disasters of various sorts but over the past six to eight months they have
been triaging opportunities instead. Sandler added that the opportunities
being offered are difficult; "it's not like people are saying 'would you
like this money or that money?'".
The opportunities he is describing are not really about money, Kühn said,
but provide ways "for activists to get stuff done and to engage
people". Over the past six months or so, SFC has successfully engaged
with "an entire community of enthusiasts", which only had a passing
familiarity with FOSS, on a multitude of
freedom-centric topics: "free software, free culture, free
creation". That is exciting, but he was getting ahead of himself
because that is where the story
ends, so he wanted to go back to the beginning.
Some time ago, 3D
printing was invented, which is something that he watched from afar; a
breadboard fire when he was an undergraduate convinced him that he should
be a software-only person. He is a fan of the 3D-printing culture,
and enjoys the talks that come from it, but he does not participate. As
part of the license-violation investigation, he and Gingerich did a crash
course in the history of 3D-printing, though Gingerich already had much of
the background.
Kühn related some of what he learned, including that the hobbyist
3D-printing field started out as a curiosity. People who wanted a 3D
printer had to build one themselves, since there were no already assembled
devices on the market. Some of those who built the early printers went on
to found companies that now sell 3D printers, which is a key element in the
development of the community. Like Linux, 3D printers started as a hobby
and remained "a hobby for a long-enough period of time that the hobby
culture could not be immediately eradicated by venture capitalists".
The "wonderful thing" about 3D printing is that the people
developing the software needed to run the devices looked to the
free-software community and "thought twice" before they started
picking licenses for their code. An important piece of the tooling needed
to use these devices is a program known as a "slicer",
which turns a 3D model—some slicers also help build these models—into thin
2D slices that can be converted into the language that the printer hardware
understands. He likens that language to assembly language, which is an
oversimplification, but helps provide a conceptual framework for him.
A longtime free-software enthusiast, Alessandro Ranellucci, created a
slicer, which he called "Slic3r".
Kühn said that his only criticism of Ranellucci was his choice of the name,
which makes it hard to distinguish between the program and the overall type
of program in a talk, so Kühn used "slicer with three" to distinguish them.
The two spoke over a video chat and Ranellucci sa