Currently the FreeBSD Project suggests and uses the following text as the preferred license scheme:
The FreeBSD project strongly discourages the so-called "advertising clause" in new code. Due to the large number of contributors to the FreeBSD project, complying with this clause for many commercial vendors has become difficult. If you have code in the tree with the advertising clause, please consider removing it. In fact, please consider using the above license for your code.
The FreeBSD project discourages completely new licenses and
variations on the standard licenses. New licenses require the
approval of <core@FreeBSD.org>
to reside in the
main repository. The more different licenses that are used in
the tree, the more problems that this causes to those wishing to
utilize this code, typically from unintended consequences from a
poorly worded license.
Project policy dictates that code under some non-BSD licenses must be placed only in specific sections of the repository, and in some cases, compilation must be conditional or even disabled by default. For example, the GENERIC kernel must be compiled under only licenses identical to or substantially similar to the BSD license. GPL, APSL, CDDL, etc, licensed software must not be compiled into GENERIC.
Developers are reminded that in open source, getting "open" right is just as important as getting "source" right, as improper handling of intellectual property has serious consequences. Any questions or concerns should immediately be brought to the attention of the core team.
This, and other documents, can be downloaded from http://ftp.FreeBSD.org/pub/FreeBSD/doc/
For questions about FreeBSD, read the
documentation before
contacting <questions@FreeBSD.org>.
For questions about this documentation, e-mail <doc@FreeBSD.org>.