[533474]

You should have licensed it under AGPL; Anthropic then would have reached you to negotiate a commercial license or contribute back to the project, since AGPL forces server-side code disclosures when deployed. Without that, they can legally use, modify, and profit from it without sharing improvements or compensating you

[RMPR]

OP mentioned he took over an existing project. He would then have to track all the people who contributed in order to be able to relicense to AGPL. Even then, Anthropic would probably then write their own.

[cbm-vic-20]

[A]GPL is like kryptonite to corporations. Very few will take the risk of having to open their own code if someone made a mistake in isolating the GPLed code properly, so most ban the use of GPL for their products and services.

Anthropic would have found a different library or rolled their own, rather than taking that risk. If the library was fundamental, maybe they'd go for a commercial license, but that's usually an option of last resort.

[kellpossible2]

what's to stop them from <prompt>Recreate this library so that I can use it in my project without fear of copyright violation.</prompt> in their very own claude code?

[KronisLV]

For small enough codebases, that seems like an inevitable reality, eventually.

If you have nearly limitless compute to throw at an issue and a good enough model, then it should be able to create enough test cases to cover most aspects of the codebase (iterating thousands of times until it gets it right) and then eventually write a new implementation in a new language or a slightly different tech stack that passes all of the original tests, alongside a few more hundreds of iterations of refactoring.

I give it a decade until large orgs are doing that to avoid licensing restrictions and other liabilities.

[singpolyma3]

If you feed it the library to recreate then this seems like it would necessarily be a derivative work and thus copyright infringement. Proving that they did it may be a challenge...