Rossmann Hosts Banned Bambu Firmware Fork, Dares Lawsuit

Right-to-repair advocate Louis Rossmann is publicly hosting a banned fork of Bambu Lab 3D printer firmware, directly challenging the company's cease-and-desist demands and daring the $1 billion manufacturer to sue him. His stand drew support from major tech voices, an open-source nonprofit, and a competing hardware maker.

The Backstory: A Firmware Update That Locked Owners Out

The conflict traces back to January 2025, when Bambu Lab pushed a firmware update that fundamentally altered how its 3D printers communicate with slicing software. The update restricted third-party slicer access, forcing print jobs to route through Bambu's cloud infrastructure — even for printers operating exclusively on local networks. For owners who had purchased hardware expecting full local control, the change felt like a bait-and-switch.

Jeff Geerling, a respected open-source engineer with over one million YouTube subscribers and owner of a Bambu Lab P1S, described his response bluntly: "I blocked the printer from the Internet via my OPNsense Firewall. I stopped updating the firmware. I locked the printer into Developer mode. I deleted Bambu Studio and started using OrcaSlicer." Geerling — like many power users — was fighting to keep control over hardware he had purchased.

The Developer Who Fixed What Bambu Broke

Enter Paweł Jarczak, a Polish software developer and 3D printing hobbyist. Jarczak created a fork of OrcaSlicer — an open-source slicing application — specifically tailored to restore the direct cloud connectivity that Bambu Lab's January 2025 update had severed. His project, OrcaSlicer-bambulab, used code from Bambu's own publicly available, AGPL-licensed Bambu Studio repository. He did not reverse-engineer anything; he used the keys Bambu itself had published.

Jarczak's fork was small, serving what Geerling estimated as "0.1% of power users." But Bambu Lab responded with force.

The Cease-and-Desist

Bambu Lab's legal team contacted Jarczak privately and demanded he remove the project. The company then published a blog post titled "Setting the Record Straight on Cloud Access and Community," in which it accused Jarczak's fork of:

• Injecting "falsified identity metadata" into network communications
• "Pretending to be the official Bambu Studio client"
• Creating a "structural vulnerability" that could enable DDoS-like conditions on Bambu's servers
• Impersonation, bypass of authorization controls, Terms of Service violations, and reverse engineering

Bambu also invoked Section 1201 of the Digital Millennium Copyright Act (DMCA) — the anti-circumvention provision that carries potential criminal penalties including federal prison time.

Jarczak refuted every claim. In his public README, he wrote:

"These are very serious public accusations. 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."

Despite believing his work was legally sound, Jarczak took the repository down. Fighting a company with an estimated valuation approaching $1 billion was not a risk a solo developer could absorb.

Rossmann Enters the Fight

On May 11, 2026, Louis Rossmann — the right-to-repair activist known for his consumer advocacy and 2.6-million-subscriber YouTube channel — published a video titled "I'll put up $10,000 to teach Bambu Labs a lesson." In it, he pledged $10,000 toward Jarczak's legal defense if the developer chose to republish his code and Bambu Lab sued.

Two days later, Rossmann escalated. In a follow-up video, "Bambu Lab: I'm reposting your code & I dare you to sue me," he announced that he had rehosted Jarczak's OrcaSlicer-bambulab code on the GitHub repository of his FULU (Freedom from Unethical Limitations) Foundation. With Jarczak's explicit permission, Rossmann put his own organization in the legal crosshairs, challenging Bambu Lab to "pick on someone their own size."

The Avalanche of Support

Rossmann's stand triggered a cascade of high-profile backing:

GamersNexus, the hardware review outlet led by Steve Burke, rehosted the code on its own servers and published a blistering piece titled "Fuck You, Bambu Lab." The outlet pledged an additional $10,000 toward Jarczak's legal defense, writing: "If Bambu Labs pursues Pawel for his code, which from what our research suggests is completely within legal bounds, we will also contribute $10,000 to Pawel's defense." GamersNexus further announced it was migrating its own 3D printing operations away from Bambu and toward Prusa, having already ordered $5,000 of Prusa equipment.

Jeff Geerling published a widely-circulated blog post on May 12, 2026, titled "Bambu Lab is abusing the open source social contract," in which he declared he "would not purchase another Bambu Lab printer." He noted the irony that Bambu's own fork of PrusaSlicer had once sent user telemetry to Prusa's servers in 2022 — and Prusa had not responded with legal threats.

Snapmaker, a competing 3D printer manufacturer, donated a Snapmaker U1 tool changer — a Klipper-based, open-source machine — to Jarczak for continued development. Blayne Sapelli, Snapmaker's Head of PR, told Tom's Hardware: "We support creators, developers, and makers who contribute to the mission of democratizing the art of creation, develop open-source projects, and push the boundaries of 3D printing and maker hardware."

The Software Freedom Conservancy Steps In

On May 18, 2026, the Software Freedom Conservancy (SFC) — the nonprofit that enforces the GPL and AGPL licenses — announced a comprehensive response. The SFC confirmed two specific AGPLv3 violations by Bambu Lab:

1. The proprietary networking library: Bambu distributes libbambu_networking (as .so, .dll, and .dylib binaries) combined with AGPLv3-licensed Bambu Studio code without providing the corresponding source, a direct violation of AGPLv3 §6.

2. Imposing further restrictions: By threatening Jarczak with legal action for exercising rights granted under the AGPL, Bambu violated AGPLv3 §10¶3, which states: "You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License."

The SFC launched the "baltobu" project — a multi-repository initiative that includes reverse-engineering Bambu's proprietary networking libraries, maintaining Jarczak's OrcaSlicer fork as a canonical community project, and developing a fully AGPL-compliant fork of Bambu Studio called "Viscose." Jarczak himself agreed to collaborate with the SFC on these efforts.

The SFC also launched a fundraiser with a target of $250,007 to hire litigation counsel. By July 16, 2026, the goal was reached and exceeded, with the SFC announcing it would hire a full-time staff attorney to prepare for potential impact litigation.

The Legal Picture

Copyright attorney and YouTuber Leonard French analyzed the situation on his channel Lawful Masses, characterizing the conflict as "a textbook manifestation of what Right to Repair advocates have started calling 'progressive enclosure' — the strategy by which manufacturers across every sector use software locks to convert one-time hardware sales into ongoing monetizable services."

French and other legal observers noted that Bambu's invocation of DMCA Section 1201 appears weak: Jarczak used Bambu's own publicly released code, not a circumvention tool. The AGPLv3 — the license Bambu itself chose when forking PrusaSlicer to build Bambu Studio — explicitly permits modification and redistribution of the code. Bambu's statement that "a license for code is not a pass to our cloud infrastructure" sidesteps the fundamental question: whether using AGPL-licensed code to communicate with servers the company operates constitutes infringement.

Where Things Stand

As of July 2026, the situation remains unresolved. Bambu Lab has not withdrawn its cease-and-desist, nor has it filed a lawsuit against Rossmann, GamersNexus, or the SFC. The code remains hosted on the FULU Foundation's GitHub and on GamersNexus's servers. Jarczak, now equipped with Snapmaker hardware and backed by a $20,000 legal fund and the institutional weight of the SFC, continues his development work.

The broader significance extends beyond 3D printing. This confrontation tests a central question of the right-to-repair movement: can manufacturers use software locks and legal intimidation to control hardware after the point of sale, even when they built that software on open-source foundations? The answer, shaped by the community's unified pushback, may redefine what "ownership" means for the next generation of connected devices.