has clause is compatible license of licence software license Source code available Platform unrestricted Number of installations unrestricted Number of users unrestricted Time for use unrestricted Usage unrestricted Distribution unrestricted GNU Project Free License Type Copyleft GNU GPL v3 GNU GPL v2 Attribution required Design Science License Allyson Lister The Design Science License is a license intended to be a general "copyleft" that can be applied to any kind of work that has protection under copyright. This license states those certain conditions under which a work published under its terms may be copied, distributed, and modified. Unlike other open source licenses, the DSL was intended to be used on any type of copyrightable work, including documentation and source code. It was the first "generalized copyleft" license. This is a free and copyleft license meant for general data. THe GNU Project does not recommend it for software or documentation, since it is incompatible with the GNU GPL and with the GNU FDL; however, they consider it appropriate for other kinds of data. The DSL was written by Michael Stutz. The DSL came out in the 1990s, before the formation of the Creative Commons. According to Wikipedia, once the Creative Commons arrived, Stutz considered the DSL experiment "over" and no longer recommended its use. https://www.gnu.org/licenses/dsl.html, accessed 13 July 2016; https://www.gnu.org/licenses/license-list.html, accessed 13 July 2016; https://en.wikipedia.org/wiki/Design_science_license, accessed 13 July 2016.