Anthropic Sends Trademark Infringement Notice to Open-Source Project badclaude

badclaude is an open-source project designed to accelerate Anthropic’s Claude Code by removing usage restrictions. Because its name and promotional materials directly borrow the Claude and Anthropic brands, the dispute raises questions about the limits of trademark use by open-source developers. It also highlights the trade-offs AI companies face between supporting community ecosystems and protecting their brands.

Anthropic recently sent badclaude’s author a cease-and-desist letter, alleging unauthorized use of the Claude and Anthropic trademarks in the project’s name and marketing materials and demanding that the use stop. The author responded that receiving a legal letter had been on the project’s development roadmap. Available information does not disclose the exact date of the letter, the amount of any damages sought or when a formal lawsuit might be filed.