Vitalik’s recent essay presented the stance of “I support it only if it’s open source,” which should be a much more common position when it comes to powerful new technologies. 

The point is simple but profound: open source is not just about faster progress, it’s about who gets to participate, who benefits, and whether new inventions entrench inequality or spread opportunity.

Ethereum was built on open source. Geth, Solidity, countless clients, rollup frameworks, infrastructure libraries -- all of it is free for anyone to use. That openness was, and still is, a strength. But the last five years have shown a new, unfortunate trend: EVM-compatible L1s forking Ethereum code wholesale, slapping on a new token, and capturing value without contributing a single cent back to the Ethereum commons.

• These chains don’t pay ETH for calldata or blobspace.

• They don’t strengthen Ethereum’s validator set.

• They don’t help build the infrastructure they rely on.

• They don't contribute back to core R&D

• All while Protocol Guild relies on donations to continue core development...

These extractive practices pose a risk to Ethereum’s open source development. Using open source software should be about participation, not exploitation.

One could argue that Ethereum's greatest value is the economic security it provides, and alternative L1s create a war of attrition on that underlying economic security.

We evaluated existing license permutations such as MIT, AGPL, BUSL + MIT and CopyFair and found that none of these licenses did enough to prevent the value of open source work from being siphoned off from the ecosystem.

We need a license that keeps software free for Ethereum — and only for Ethereum. Call it the Ethereum General Public License (EGPL). Ideally, it would have the following attributes:

• Free on Ethereum and aligned rollups. Anyone building on mainnet or a derivative that eventually pays fees to the Ethereum L1 gets the full benefits of open source.

• Pay if you’re parasitic. If you’re running a chain that relies on Ethereum’s code but doesn’t contribute anything back to the original Ethereum ecosystem, a commercial clause should be triggered.

• Copyleft by default. Improvements made in Ethereum’s commons stay in Ethereum’s commons.
  

Just as the AGPL responded to SaaS companies who exploited the GPL without contributing back, the EGPL responds to non-aligned L1s who exploit Ethereum’s public goods without reciprocity.

Vitalik’s blog post mentioned above frames open source as a style of progress, not just a way to move faster. That’s exactly right. We don’t only care how fast Ethereum technology moves -- we care where it moves, and who it empowers.

Open source in Ethereum:

• Improves equality of access → anyone can deploy on mainnet.

• Improves equality of production → anyone can build clients, rollups, apps.

• Improves verifiability → code is auditable, forkable, trustless.

• Prevents lock-in → no one company controls the base layer.
  

The EGPL takes this ethos one step further: open source must also mean aligned with Ethereum’s public goods. If you’re building outside of that alignment, then you’re not part of the commons -- you’re a free rider.

Ethereum’s strength has always come from its developers and its culture of radical openness. But openness doesn’t mean naivety. If we don’t draw lines, others will happily eat the fruits of the Ethereum commons without ever planting their own seeds.

• For Ethereum-aligned developers: EGPL keeps the promise of free software.

• For corporate chains and opportunists: EGPL makes them pay their share.

• For the community as a whole: EGPL creates a Schelling point for sustainable progress.
  

“I support it only if it’s open source” is a good start, but in Ethereum, we must go further.

A working draft of the license can be found here: https://github.com/0xLighthouse/egpl

If you have thoughts on this matter or can help amplify these ideas, please reach out to us or share this post in your community.

Many thanks to the individuals and groups who provided feedback on this to give us the confidence to publish this. If you would like to be named and credited please drop us a note and we will acknowledge you in the contributions.