Bonsai Licensing Explained: Is It Really Free Forever?

published on 08 February 2025

The open-source world is revolutionizing industries, and the Architecture, Engineering, and Construction (AEC) sector is no exception. One of the most intriguing projects in this space is Bonsai, a next-generation IFC-native authoring tool that evolved from the BlenderBIM Add-on. Many people ask: Is Bonsai really free forever? Let’s break it down.

The Legal and Business Framework of Bonsai

Bonsai operates under a dual open-source licensing model:

  1. LGPL (Lesser General Public License) – Covers the IfcOpenShell library that Bonsai is built on.
  2. GPL (General Public License) – Covers Bonsai itself.

What Do These Licenses Mean?

  • Bonsai is Free Forever: The GPL license ensures that Bonsai will always remain free and open-source.
  • Companies Can Sell and Modify Bonsai: Businesses can modify, rebrand, and even sell Bonsai legally. However, they must provide the modified source code to users.
  • No One Can Revoke Access: Once you download Bonsai, you own that version permanently, even if the project ceases development.
  • Collaboration is Encouraged: Any improvements made to Bonsai must also be shared openly, fostering a community-driven development model.

Can Bonsai Become a Paid Product?

No, and here’s why:

  1. GPL ensures transparency: Anyone who buys a modified version of Bonsai can legally share it for free.
  2. The license cannot be changed without unanimous agreement: Over 200 contributors have worked on Bonsai, and all of them would need to agree to any license change.
  3. The software can always be redistributed: Even if Bonsai were to start charging for downloads, anyone with a copy could legally share it for free.

How Can Businesses Profit from Open-Source Software Like Bonsai?

While Bonsai itself is free, companies can still make money in various ways:

  • Offering support and training services – Providing premium customer support for Bonsai users.
  • Custom development – Businesses can build specialized features for their own needs.
  • Cloud hosting and integrations – Charging for cloud-based collaboration features.
  • Enterprise solutions – Offering tailored solutions for large firms.

How is Bonsai Financially Sustainable?

Bonsai is primarily supported by donations and community funding. Currently, the project receives around $3,000 per month, allowing developers to maintain and improve the software. With increased adoption, this funding could grow, ensuring Bonsai’s long-term sustainability.

What’s Next for Bonsai?

As Bonsai’s user base grows (currently estimated at 880,000+ downloads per year), its financial model may evolve. Potential future developments include:

  • More enterprise support services
  • A broader developer ecosystem
  • Greater integration with industry workflows

Conclusion: The Power of Open-Source BIM

Bonsai represents a major shift in how AEC software is developed and distributed. Its open-source nature ensures that it remains accessible, transparent, and community-driven, unlike proprietary BIM tools. Whether you are an architect, engineer, or software developer, Bonsai provides an opportunity to participate in shaping the future of openBIM.

If you believe in open-source BIM software, consider contributing through funding, development, or simply spreading the word!

You can check out the video from BIMvoice discussing this below.

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