Copyleft, All Rights Reversed

I want my blog to be used for education, training, and research. I hope that its contents appear in derivative works such as other blogs, websites, and wikis. I'd prefer that these derivative works be openly shared.

I would also ask that any material that is repurposed has attribution to me as the author.

Content from my blog should not be sold. Charging for access to that which I make freely available seems wrong.

How do I express these preferences legally?

There are a variety of licensing approaches that enable the author to declare preferences beyond "(c) copyright all rights reserved". In my case, I want "some rights reserved".

I recently me with the CEO of Wikidoc, a community supported medical reference, and he handed me a presentation with the term "Copyleft".

What is Copyleft? From Wikipedia:

"Copyleft is a form of licensing and can be used to modify copyrights for works such as computer software, documents, music and art. In general, copyright law allows an author to prohibit others from reproducing, adapting, or distributing copies of the author's work. In contrast, an author may, through a copyleft licensing scheme, give every person who receives a copy of a work permission to reproduce, adapt or distribute the work as long as any resulting copies or adaptations are also bound by the same copyleft licensing scheme. A widely used and originating copyleft license is the GNU General Public License. Creative Commons provides a similar license called ShareAlike."

Creative Commons licenses contain four major permissions:

* Attribution (by) requires users to attribute a work's original author.
* Share-alike (sa), which is a copyleft requirement that requires that any derived works be licensed under the same license,
* No derivatives (nd), which requires that the work not be modified.
* Non-commercial (nc) requires that the work not be used for commercial purposes.

There's an automatic license generator on the Creative Commons site. I entered my preferences as

Allow commercial uses of your work - No

Allow modifications of your work - Yes, as long as others share alike

And it generated the License that now appears in the upper right hand corner of my blog - "Life as a CIO Blog by John D. Halamka MD is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License."

Now you can feel free to use my blog under Creative Commons license. Help yourself.