A fork of Bambu Studio created because the original focused on Bambu's own printers and ignored everyone else. It became the de facto standard slicer for the entire open-source 3D printing community - until Bambu's 2025 lockdown and a 2026 copyright crackdown turned the relationship toxic.
A C++/Qt slicer derived from Bambu Studio, itself derived from PrusaSlicer (GPL lineage, now AGPLv3). The fork differs mainly in UI, calibration tools, and printer profile support. The legal conflict centers on Bambu's use of AGPLv3 code in closed-source firmware components and the threat of a C&D against a compatible fork - both open questions in a lawsuit era for the 3D printing industry.
Bambu Studio, released in 2022 by 3D printing giant Bambu Lab, is itself a fork of PrusaSlicer with a heavily customized UI. In July 2022, developer SoftFever forked it back out: he liked the software but found the UI opinionated and Bambu's development focused exclusively on its own printers, with the broader Voron and RepRap communities locked out. The fork, renamed OrcaSlicer in March 2023, added the features the community wanted - better calibration, more printer profiles, more control - and quickly became the default slicer for anything not made by Bambu, adopted in turn by Creality, Elegoo, Anycubic, and others for their own printers.
In January 2025, Bambu shipped a firmware update that required its own proprietary 'Bambu Connect' app for cloud printing, effectively locking third-party software out of its printers. OrcaSlicer responded by refusing to integrate with the lock-in, saying: 'We encourage Bambulab to reconsider their current policy.' In April 2026, Bambu escalated: it threatened legal action against a volunteer who had made a fork of OrcaSlicer that supported Bambu printers, forcing him to take the repository down. The Software Freedom Conservancy then investigated Bambu Lab's use of AGPLv3 code and issued a public statement, and SFC's Bradley Kuhn called it 'the most egregious AGPLv3 violation that I have ever seen'.
SoftFever creates a fork of Bambu Studio.
The fork is renamed OrcaSlicer with release 1.5.0.
Bambu Lab ships its 'Access Control System' lockdown, restricting third-party printing apps.
OrcaSlicer refuses to integrate Bambu Connect, publicly urging Bambu to reconsider.
Bambu sends a cease-and-desist to the maintainer of OrcaSlicer-bambulab, who removes the fork.
The Software Freedom Conservancy announces a compliance campaign over Bambu's AGPLv3 violations.
“We encourage Bambulab to reconsider their current policy.”
“Bambu Lab has sent me a cease and desist letter; I removed the repository.”
“This is the most egregious AGPLv3 violation that I have ever seen.”
OrcaSlicer became the community's insurance policy against printer lock-in, and Bambu's attacks on it became the 3D printing world's defining open-source battle. The C&D backfired in spectacular fashion: the SFC's public campaign and the 'egregious' quote turned a niche licensing dispute into mainstream coverage, and the open-source slicing ecosystem is now rallying around it.