The first hardware-focused Open Source activities started around 20 years ago. But even as open hardware itself matures, the legal aspects remain relatively unexplored, and many unanswered legal questions remain. We'll examine what "licensing" means in terms of hardware, and discuss the adequacy of currently available mechanisms to express the intent of the authors and creators of open hardware. From our experience in Open Source software, we naturally attempt to find parallels in software licenses that can be applied to hardware; however, hardware designs introduce new aspects that have no equivalent in the software world.

In particular, we're especially interested in how the ideas and principles of copyleft translate. How do things like linking, derivative works, and compilation operate in terms of hardware? What "exclusive rights" belong to authors and makers in this domain, and can we offer a license to those rights the same way we can for software copyrights? What rights do builders/fabricators have? How does a license on a digital description affect the manufacture, distribution, and copying of the corresponding physical objects it describes? How do the various types of components within an open hardware design interact, and how do the licenses of those components interact over the many ways of connecting those components together? And can we apply or adapt existing Open Source software licenses for hardware, without fragmenting the ecosystem between software and hardware, especially as the lines between the two become increasingly fluid?

We'll explore each of these areas, using as a case study the creation, licensing, and distribution of a product incorporating both open software and many types of open hardware. We'll offer our thoughts on some possible properties of an ideal open hardware licensing framework, seek consensus on how our principles apply in various concrete scenarios, and invite discussion on how our legal structures can adapt to serve the needs of the developing Open Source hardware world.