Recommended Open Hardware Licenses
According to openhardware.org: , Nov 2011:
"It is strongly recommended that you use the licenses in this list. The Recommended Licenses have been chosen to provide a minimal set of licenses, which are all compatible with each other, and which thus reduce the legal load upon the entire community. When you choose a license that isn't on the recommended list, you increase the legal load to developers and users unnecessarily.
The list of recommended licenses has not yet been determined. In the interim, we recommend that you use the TAPR Open Hardware License, Creative Commons BY-SA 3.0, or GPL 3.0 .
The final list will be settled upon using the Recommended License List Process.
Note that Hardware Isn't Generally Copyrightable. Thus, there are severe limitations upon the enforcement of the licenses of hardware designs that do not exist for licenses applied to software." (http://wiki.openhardware.org/Recommended_Licenses)