Ethereum co-founder Vitalik Buterin is urging the crypto industry to embrace “copyleft” open-source licenses, voicing concern that the space is drifting away from its collaborative origins.
In a blog post published Monday, Buterin explained that while he once supported a more “permissive” licensing model—which allows anyone to freely share, modify, and distribute code—he has recently grown more supportive of the “copyleft” approach.
The key distinction lies in how future use is governed: both license types permit public use and modification, but copyleft licenses require that any derivative works also be open-sourced under the same terms.
“I generally philosophically dislike copyright and patents,” Buterin wrote.
Buterin embraces copyleft approach to open-source licensing
“I dislike the idea that two individuals privately exchanging data could be seen as violating the rights of a third party they’re neither affecting nor communicating with,” Buterin noted.
He explained that his growing support for “copyleft” stems from the fact that open source has now gone mainstream, making it more feasible to encourage enterprises to adopt such licenses.
Still, Buterin acknowledged that copyleft licenses can have drawbacks—particularly their potential to be overly restrictive or coercive, especially in scenarios where code isn’t publicly distributed but still needs to be shared.
Copyleft in the crypto industry
Buterin pointed out that the crypto space has grown more competitive and less collaborative over time, eroding the original open-source ideal of freely and voluntarily sharing code.
“The crypto space in particular has become more competitive and mercenary, and we are less able than before to count on people open-sourcing their work purely out of niceness.”
Buterin argued that voluntary sharing is no longer sufficient and needs to be reinforced by the “hard power” of granting code access only to those who are willing to open up their own.
He emphasized that copyleft licensing enforces reciprocity in the crypto space, helping ensure that innovation serves the broader community rather than just a few closed-source players.
Ultimately, he concluded, copyleft helps build a “large pool of code” — or other creative works — that can only be legally used if contributors agree to share the source code of whatever they create from it.
“Hence, copyleft can be viewed as a very broad-based and neutral way of incentivizing more diffusion, getting the benefits of policies like the above without many of their downsides.”
Incentivizing open source is most effective when it strikes a balance—neither unrealistic nor assured—Buterin said, noting that the advantages of copyleft licensing are significantly greater now than they were 15 years ago.
Crypto venture capitalist Adam Cochran agreed, stating, “There are some practical edge cases where copyleft can be problematic, but overall I align with the philosophy.”
