Bambu Lab Threatens Legal Action Against Open Source Fork

Key Takeaways

• Bambu Lab sent legal threats to the developer of OrcaSlicer-bambulab for bypassing their cloud printing system
• The fork uses code from Bambu Studio, which is itself AGPL-licensed open source software
• Bambu Lab accused the developer of 'impersonation attacks' but refused to publish full correspondence

The Fork That Started a Fight

Bambu Lab, the Chinese 3D printer maker known for its fast, reliable machines, has picked a fight with a small open source project. The company sent legal threats to the developer behind OrcaSlicer-bambulab, a fork that allows users to print without routing files through Bambu's cloud servers.

The irony runs deep. Bambu Studio, the company's own slicer software, is a fork of Prusa Slicer, which is a fork of slic3r. All are licensed under AGPLv3, an open source license that explicitly permits forking and modification. OrcaSlicer itself is a fork of Bambu Studio. The contested OrcaSlicer-bambulab fork simply extends that chain.

According to Jeff Geerling, a prominent tech commentator who detailed the controversy, Bambu's default setup sends every file you print through Bambu's servers. The company can see everything you print on your printer. For the small percentage of users who want to avoid this, OrcaSlicer-bambulab offered a workaround using code that already exists in Bambu's own AGPL-licensed software.

What Bambu Lab Accused the Developer Of

Bambu's legal threat included serious accusations. The company claimed the fork used an 'impersonation attack' against their infrastructure. They suggested the developer was bypassing security and creating risks to their systems.

“Bambu Lab did not write to me with these specific public claims first. They also refused my request to publish the full correspondence. Instead, they published a one-sided public statement where I cannot reply directly. In practice, this presents me to the public as someone bypassing security, impersonating their client, and creating a risk to their infrastructure. I reject that characterization.”

— OrcaSlicer-bambulab developer

The developer's response highlights a key fact: the fork uses Bambu Studio's upstream code verbatim. If there's an 'impersonation attack' in the code, it exists in Bambu's own open source project.

Why Users Want to Bypass Bambu's Cloud

For most users, Bambu's cloud printing is convenient. You can start a print from anywhere without managing your own VPN or network setup. But for privacy-conscious users and those who want full control over their hardware, the mandatory cloud connection is a dealbreaker.

Geerling describes his own setup: he blocked his P1S printer from the internet via his OPNsense firewall, stopped updating the firmware, locked the printer into Developer mode, and switched from Bambu Studio to OrcaSlicer. He runs his own WireGuard VPN for remote access.

This is overkill for most people. But Geerling's point stands: he paid for the hardware and wants to own what he purchased, not have the company watching everything he does with it.

The Open Source Social Contract

The AGPLv3 license exists for exactly this kind of situation. When Bambu forked Prusa Slicer to create Bambu Studio, they inherited obligations. They must release their modifications under the same license, and others can fork their code in turn.

This is the 'social contract' Geerling references. You take from the open source community, you give back. You benefit from others' work, you let others benefit from yours. Using legal threats to suppress a fork that uses your own AGPL code breaks that contract.

Bambu could have engaged with the developer directly. They could have published the full correspondence. They could have pointed to specific license violations if any existed. Instead, they made public accusations while refusing transparency.

What This Means for Bambu Owners

If you own a Bambu printer and use the default cloud setup, nothing changes for you. The convenience remains, as does Bambu's ability to see your print files.

If you're part of the small percentage who wants local-only printing, your options are narrowing. Geerling's workaround requires technical knowledge and old firmware. The OrcaSlicer-bambulab fork now faces legal pressure. Bambu appears committed to closing these doors.

The broader issue is trust. Bambu built a reputation on excellent hardware and competitive prices. But their recent moves, including pushing always-connected cloud as the default, suggest priorities that may not align with users who value ownership and privacy.

Frequently Asked Questions

Can I still use a Bambu Lab printer without cloud connectivity?

Yes, but it requires technical steps: blocking the printer at your firewall, staying on old firmware, and running in Developer mode. Bambu is making this harder with each update.

What is OrcaSlicer and is it safe to use?

OrcaSlicer is an open source slicer software forked from Bambu Studio. It's widely used in the 3D printing community and is considered safe, though forks like OrcaSlicer-bambulab now face legal pressure from Bambu.

Does Bambu Lab really see everything I print?

If you use their default cloud printing setup, print files route through Bambu's servers. The company has access to this data. Local printing options exist but require technical workarounds.

What is the AGPL license and why does it matter here?

The AGPLv3 is an open source license that requires derivative works to be released under the same license. Bambu Studio uses code from Prusa Slicer under AGPL, which means others can legally fork Bambu Studio.

Source: Hacker News: Best