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What does the PrusaSlicer AGPL violation actually look like? PS is licensed under AGPL-3.0. That's the strongest copyleft license there is. It's simple: you can fork it, you can build a business on it, you can ship it commercially. But any derivative work has to stay open source too. You take from the community, you give back to the community. That's the social contract. PS is a fork of Slic3r and even though 90+% of the codebase is now written by us, we are proud about the heritage. BambuStudio (BS) is a fork of PrusaSlicer (PS). They published the slicer parts, that's fine. The networking plugin, the part that actually talks to their cloud, is closed-source. Just a binary black-box. The standard defense for something like this is "the plugin is a separate work, so it's not subject to copyleft." That argument falls apart on contact with the actual software. BS cannot do its primary job without the plugin. The plugin cannot do anything without BS. They are not two products that happen to talk to each other, they are one product split across two files for PR license-laundering convenience 😒 Under AGPL, that's still a violation. You don't get to keep the copyleft piece closed by moving it across a function call boundary and calling it a separate work. The license they inherited from us doesn't allow that. The OrcaSlicer inherited the same license by forking BS and follows the rules. Most people miss that the networking blob isn't even bundled inside BS. It downloads itself at runtime. So you can audit BambuStudio's open source code all you want. You cannot meaningfully audit the part that actually talks to the cloud. It lives outside the published software supply chain, arrives from a CDN you don't control, and can be replaced from one launch to the next without anyone outside Bambu having a chance to look at it first 😬 I flagged this exact architecture publicly in March 2023. The same architecture is in place today. xcancel.com/josefprusa/status/1634… Back then we considered legal action. We seriously did. But the practical reality: PrusaSlicer is software, not hardware. There's no boxed product crossing customs to stop - only real possibility which would make them comply. And jurisdiction for the licensee lands in China, which means the case lands in a Chinese court applying Chinese law to a Chinese company. The AGPL is a license. A license without a viable enforcement path is, in practice, a suggestion. So Bambu got away with it. The networking blob kept doing whatever it does. And many “we are sorry”s later we land here today - legal threats to a small developer opening their tiny black box 🤦‍♂️ 3/x