The Arbitrum Expansion Program (AEP) sets forth permissive software terms of use tailored for projects that want to use Arbitrum technology to create their own custom Arbitrum chains.

The AEP aims to foster innovation while maintaining specific conditions to protect the Arbitrum ecosystem. It builds on the existing Business Source License with an “Additional Use Grant.” 

This means developers building chains that settle onto Arbitrum One or Nova can freely use, modify, and adapt Arbitrum technologies for their unique needs without incurring royalties or fees* while retaining all the advantages of being a member of the Arbitrum ecosystem. Key benefits of the AEP include:

• Battle-tested technology: Developers are free to use battle-tested and reliable Arbitrum technology to launch Arbitrum One or Nova chains without royalties or fees*, fostering accessibility and lowering barriers to entry for blockchain projects.
• Entirely customizable: The terms of use allow modifications and customizations of the Orbit technology, enabling developers to tailor it to specific use cases while maintaining compliance with its terms.
• Ecosystem support: Arbitrum  chains built under the AEP will benefit from the interoperability and community support of the broader Arbitrum ecosystem while ensuring the integrity of their network through specific usage conditions. 

*While permissive, any L3 chain that chooses to settle onto parent chains other than Arbitrum One or Nova will be required to contribute 8% of its net chain revenue to the Arbitrum DAO and 2% to the developer guild.

Overall, the AEP terms of use provides a developer-friendly framework that accelerates innovation and adoption while safeguarding the Arbitrum ecosystem. For more detailed insights, visit the official AEP terms page.