An open source license grants rights in copyrighted code: copy it, modify it, redistribute it. It says nothing about the project's name or logo, because those are trademarks, a different kind of property governed by a different policy that the copyright license does not touch. The binder keeps this sheet because the gap between the two instruments has produced some of the culture's longest-running disputes, usually between a project and its own most faithful redistributors.

The code can be entirely free while the name stays entirely reserved, and both things are true on purpose. The mark usually belongs to whoever stewards the project, often a company or the kind of nonprofit described on the sheet about what a foundation holds, and that owner, not the license, decides who may put the name on a build. Three well-documented cases, Firefox in Debian, Chromium and Google Chrome, and the OpenOffice.org split, show the same pattern from three different directions.

Why does a project need a separate trademark policy at all?

A trademark identifies the source of a product to the people using it: when you see the name, you expect a particular thing. If anyone could build a modified version of a program and still call it by the original name, the mark would stop meaning anything, and users would have no way to tell an official release from a stripped-down or altered one. So most serious open source projects, once they are large enough to be worth copying, write a trademark policy that sits beside the copyright license: the code is free to fork, but the name and logo travel with conditions the copyright grant never covered.

What happened when Debian redistributed Firefox?

Mozilla's trademark policy required that builds carrying the Firefox name and logo either be the official binary or be approved by Mozilla, including how security patches were applied. Debian's practice is to patch any package, security fixes included, on its own schedule, without asking an outside party for sign-off first, and the Firefox artwork itself was under a copyright license Debian did not consider free. The two requirements could not both be satisfied on the same build, and from 2006 until 2016 Debian shipped its own compiled version of the Firefox source code under a different name, Iceweasel, with a redrawn logo, specifically because it could not meet Mozilla's trademark conditions while keeping its own patching freedom. The underlying code was the same free software either way; the name was the thing that could not travel with it unmodified.

Why is Chromium not the same product as Google Chrome?

Google publishes the Chromium project's source code under a permissive, BSD-style license, and anyone can download, build, and redistribute it freely, which is exactly what several other browsers do. Google Chrome is Google's own build of that code, carrying the Chrome name, the Chrome logo, and a set of additions, including automatic updates and usage statistics, that are not part of the open Chromium source. A person can build the open code tonight, but cannot call the result Google Chrome or use Google's branding on it, because the name and the proprietary layer around it sit outside the license that covers the shared code underneath.

What happened to OpenOffice after Oracle bought Sun?

When Oracle acquired Sun Microsystems in 2010, a group of the project's own contributors, uncertain about Oracle's commitment to the office suite, formed the Document Foundation and forked the codebase under a new name, LibreOffice, later that same year. The original OpenOffice.org name and trademark stayed with Oracle, which went on to donate the code to the Apache Software Foundation, where it continues as Apache OpenOffice. Two active, separately named projects now trace back to the same source tree, under compatible open licenses, because the trademark on the original name did not travel with the community that kept developing the code. The fork needed a new name precisely because the old one was never the forking community's to keep.

What this means for a reader of any license

A reader who checks a license for permission to redistribute, modify, or sell software and stops there has checked only half the instrument that actually governs a project. The other half, the trademark policy, usually lives on a separate page, is rarely required reading, and is the part that decides whether a derivative work can keep the name everyone already recognizes. The three cases on this sheet share one shape: the code stayed free, the derivative stayed legal, and the name still had to change, because a copyright license was never the document that was protecting it.

What the text grants

A copyright license grants rights in the code. It says nothing about the project's name, logo, or other marks, which are governed by a separate trademark policy.

What a reader should check

Whether the project publishes a trademark policy apart from its license, and what it requires of a build that keeps the original name.

The limit of this reading

Trademark policies vary by jurisdiction and by project; none of the three cases here is a universal rule for how a given name dispute will resolve.