CoinWorld.net reported on April 16 that Ethereum co-founder Vitalik Buterin responded on the X platform to developer raulk's discussion about open-source licenses. He stated that copyleft licenses can serve as a strong self-regulation mechanism to prevent future project versions from becoming closed source—unless the cost of a complete rewrite is undertaken, and even then, there may be legal risks related to derivative works. Previously, raulk suggested that in the era of AI agents and "vibe coding" (interacting with AI to generate code based on intuition), the protective role of copyleft licenses in preventing open-source code from being exploited in closed-source projects is weakening, as attackers can reverse engineer through LLM behavior and re-implement, bypassing GPL obligations.