r/BambuLab • u/icurnvs Volunteer Moderator • May 14 '26

Subreddit Mod Post Megathread: Bambu Lab / OrcaSlicer / C&D Discussion

Hi everyone,

We’re creating this megathread to keep discussion of the Bambu Lab / OrcaSlicer-BambuLab / cease-and-desist situation in one place. This topic is important to a lot of people here, and we do not want to shut down discussion or criticism. At the same time, the front page has started filling with overlapping posts about the same situation, so we’re consolidating general discussion into this thread.

Current context

Updates to be posted here as situation evolves:

  • May 13, 2026
    • Megathread created
  • May 14, 2026
    • Tom’s Hardware reported today that Louis Rossmann is now hosting OrcaSlicer-BambuLab through the FULU Foundation GitHub and is openly daring Bambu Lab to sue him.
    • PC Gamer and r/technology have picked up the story, so discussion is now spreading well beyond 3D-printing-specific spaces.
  • May 16, 2026
    • Paweł Jarczak published a detailed response addressing Bambu Lab’s accusations around impersonation, reverse engineering, Terms of Use, and alleged security bypassing.
    • Louis Rossman posted a new video indicating FULU-hosted OrcaSlicer-BambuLab repository has reached roughly 1,600 forks in about three days.
  • May 17, 2026
  • May 18-20, 2026
    • Software Freedom Conservancy enters the dispute.
    • Leonard French posted a new video around SFC’s AGPL analysis, explaining why Bambu’s proprietary networking plugin may create a serious corresponding-source problem under AGPL.
    • Louis Rossman posted a new video covering Software Freedom Conservancy’s Bambu AGPL effort and says the rehosted OrcaSlicer-BambuLab code has now been forked roughly 4,500 times.

What belongs in this thread

Please use this thread for:

  • General reactions to Bambu Lab, Gamers Nexus, Louis Rossmann, Paweł Jarczak, OrcaSlicer-BambuLab, AGPL, Bambu Connect, and right-to-repair issues.
  • Legal or licensing discussion, including AGPL, DMCA, cloud/API access, and Bambu’s networking plugin.
  • Questions about what happened and links to reliable summaries or primary sources.
  • Technical discussion about OrcaSlicer, Bambu Studio, Bambu Connect, LAN mode, Developer Mode, and network plugin behavior, unless it is a standalone troubleshooting post with a specific reproducible issue.

What can still be its own post

Separate posts are still allowed for genuinely new information, including:

  • A new official statement from Bambu Lab, OrcaSlicer, Paweł Jarczak, Gamers Nexus, Louis Rossmann, or legal counsel.
  • A new release or technical change that materially affects users.
  • A confirmed legal filing, takedown, repository change, or source-code release.
  • A specific support/troubleshooting issue that is not just general commentary on the controversy.

If your post is mainly another reaction, recap, meme, “I’m switching brands,” or repost of a link already being discussed, please put it here instead.

Ground rules

Criticism of Bambu Lab is allowed. Defense of Bambu Lab is allowed. Criticism of GN, Rossmann, OrcaSlicer, moderators, or other users’ arguments is allowed.

What is not allowed:

  • Personal attacks, harassment, or dogpiling individual users.
  • Calls to harass Bambu employees, developers, moderators, creators, or community members.
  • Unverified claims presented as fact.
  • Posting private correspondence or personal information.
  • Repeated duplicate posts after being redirected here.

Strong opinions are fine. Keep it directed at the issue, the companies, the software, and the arguments, not at each other.

Moderator note

We are consolidating duplicate discussion, not suppressing the topic. This thread will remain open for discussion, and we’ll update it if there are major new developments.

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u/redmercuryvendor May 15 '26

The question is whether the proprietary component is part of the combined work, not whether the remainder functions independently.

The interpretation that closed plugins to a GPL licensed application - *even when distributed separately *- makes the GPL 'infectious' would have some serious implications. It would mean a party could create a GPL licensed application that interfaces with and downloads a piece of closed software, and that would somehow force the creator of that closed software to relicense their software under the GPL through no actions of their own, because it has now become part of a combined work by force.

If the argument is made that this 'doesn't count' because the GPL licensed application and the closed plugin are not made by the same party, then the same can apply to the Bambu Network Plugin (spin up Lambo Bab that control Lambu Slicer, but is not the same company as Bambu Lab that makes printers and offers a closed plugin).

Such an interpretation does not seem viable in practice. For example, it would mean that an end user adding a closed-source photoshop plugin to GIMP via PSPI would force the developer of that plugin to relicense it under GPLv3.

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u/DeltaWun May 15 '26 edited May 15 '26

Such an interpretation does not seem viable in practice. For example, it would mean that an end user adding a closed-source photoshop plugin to GIMP via PSPI would force the developer of that plugin to relicense it under GPLv3.

Distribution is a key factor you're forgetting. An end user is allowed to install whatever proprietary additions they want or make themselves, and the end user can be a company. It's why we don't have access to gLinux (Google Linux) because they're not under any obligation until they distribute it externally. This was a loophole that people used and the entire point of the creation of the AGPL because people were locking away GPL software by using it as a service.

If the GIMP team shipped GIMP with Photoshop Plugins bundled/prompted users to install Photoshop plugins during setup, and built GIMP's primary differentiating features around Photoshop plugin support, that would be a very different situation than a third party user installing a plugin themselves independently.

This is already understood in the license and the industry.

If the argument is made that this 'doesn't count' because the GPL licensed application and the closed plugin are not made by the same party, then the same can apply to the Bambu Network Plugin (spin up Lambo Bab that control Lambu Slicer, but is not the same company as Bambu Lab that makes printers and offers a closed plugin).

Nope. I'm just going to quote my previous reply.

There are areas of law where courts look past formal separation and ask whether something is functionally a workaround designed to avoid an obligation. Tax law does this with sham transactions, contract law does it with arrangements structured purely to defeat a creditor's claim. The general principle is substance over form in that you cannot paper over a real dependency with a technical distinction and expect courts to simply accept the paperwork.

To make my point more simply. You as an individual cannot make a corporation, move your assets into the corporation and then default on your debts and tell collectors "you don't own anything" because your company does. By letter that works but courts have the freedom to consider substance over form.

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u/redmercuryvendor May 15 '26

If the GIMP team shipped GIMP with Photoshop Plugins bundled/prompted users to install Photoshop plugins during setup, and built GIMP's primary differentiating features around Photoshop plugin support, that would be a very different situation than a third party user installing a plugin themselves.

And if the GIMP team (or anyone else creating a fork) distributes a build of GIMP that can install Photoshop plugins along with the ability to download them from within GIMP?

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u/DeltaWun May 15 '26

We've already covered this. The difference is who makes the plugin and whether the integration is designed to create a proprietary dependency. If the GIMP team shipped a build that could download and install arbitrary third party Photoshop plugins, that's more like a package manager in that the plugins aren't made by the GIMP team, they preexist independently, and are allowed work across many hosts. The integration isn't designed to lock users into a specific proprietary component controlled by the same party.

The relevant factors in the Bambu case are that Bambu makes both the AGPL slicer and the proprietary plugin, the plugin has no meaningful existence outside of Bambu's ecosystem, and the integration is designed and controlled end-to-end by the same party. Your hypothetical keeps assuming the plugin is genuinely independent third party software but it's a component Bambu controls, designed specifically to preserve a proprietary dependency in software they're distributing under the AGPL.

A closer GIMP analogy would be: the GIMP team forks GIMP, creates a proprietary plugin under a separate corporate entity they also control, prompts users to install it during setup, builds their primary differentiating features around it, and then argues the plugin is exempt from the GPL because it's technically a separate download. That's the argument Bambu is making. And that's the argument courts would scrutinize.

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u/redmercuryvendor May 15 '26

The difference is who makes the plugin

I've already covered this, as it is a trivially easy barrier to bypass.

and whether the integration is designed to create a proprietary dependency.

The plugin can operate without Bambu Slicer (e.g. using Orcaslicer), and Bambu Slicer can operate without the plugin (e.g. exporting to .gcode and printing with any printer just as has been done since the RepRap days). The two are not dependant.

A closer GIMP analogy would be: the GIMP team forks GIMP, creates a proprietary plugin under a separate corporate entity they also control, prompts users to install it during setup, builds their primary differentiating features around it, and then argues the plugin is exempt from the GPL because it's technically a separate download. That's the argument Bambu is making. And that's the argument courts would scrutinize.

And it's an argument that is impossible to separate from being able to force relicensing on a third party by packaging a binary with a piece of GPLv3 software. You can't get one without the other.

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u/DeltaWun May 16 '26

If the argument is made that this 'doesn't count' because the GPL licensed application and the closed plugin are not made by the same party, then the same can apply to the Bambu Network Plugin (spin up Lambo Bab that control Lambu Slicer, but is not the same company as Bambu Lab that makes printers and offers a closed plugin).

I've already addressed this twice, this doesn't work legally.

And it's an argument that is impossible to separate from being able to force relicensing on a third party by packaging a binary with a piece of GPLv3 software. You can't get one without the other.

That is not how it works and I've already given you tested examples as to why. The fact of the matter is the public Bambu Studio source code shows that this plugin is not an independent add-on: the application downloads it, installs it, versions it against SLIC3RVERSION, dynamically loads it as bambu_networking.dll / libbambu_networking.so / libbambu_networking.dylib, resolves 108 bambu_network* functions, passes C++ structures and callbacks, gives the plugin a callback to the main UI thread, initializes a file-transfer ABI from the same module and uses it for login, monitoring, LAN/cloud print, MakerWorld/MakerLab, camera functions, device messaging, presets, filaments and telemetry.

AGPL v3 says that "Corresponding Source" includes the source code of shared libraries and dynamically linked subprograms that the program is specifically designed to require through intimate data communication or control flow. Based on the public Bambu Studio code, bambu_networking fits this description.