There is an understandable desire for credit for creating open source projects. This generally manifests as a requirement that attribution in code may not be removed. Occasionally this desire manifests as imposing a duty to display or retain a trademark in modifications. The OSI-approved Common Public Attribution License Version 1.0 includes a provision like this, as does the FSF-approved Yahoo! Public License Version 1.1. There are still efforts to include these types of provisions, for example, the Beanbooks Public License is another attempt.

This appears to arise because there was an over-expansive interpretation of "attribution" to include "trademark." The talk will discuss the qualitative differences between the two and argue that license that require the use of trademarks are not free licenses under either the Four Freedoms or the Open Source Definition.