Last month a maintainer friend pinged me at 2 a.m. asking what to do about a cease-and-desist letter. They had forked a popular open-source project, kept the original name with a -community suffix slapped on the end, and the upstream company's lawyers were not amused. The code was MIT-licensed. The trademark was not.

This is the kind of problem that catches every first-time forker off guard. You read LICENSE , see something permissive, and assume you're free to do whatever you want. You are — with the code. The brand, the logo, the project name? Those are a completely different legal animal, and getting them wrong can sink your fork before it ships its first release.

Let me walk through how I've helped a few maintainers untangle this, and how to avoid it in the first place.

The problem: a permissive license is not a permissive brand

Here's the scenario.…