Development of Creative Commons licenses

["Watanabe Tomoaki" <tomoaki_watanabe_cc AT hotmail.com>]

Dear list participants;

I have a simple question regarding the difference between cc-by and 
cc-by-sa. It seems that when I create a derivative work (say, an 
encyclopedia article) based on someone else's cc-by contents (say, a 
instructional material for school teachers), I can release that derivative 
work (article) under any license, as long as I include attribution to the 
authors of the work I used (the instructional material). 

I may release it with fully copyrighted, or I may use other CC license, or 
some other copyleft licence, etc.

However, if the instructional material is provided under "cc-by-sa" 
license, the article must be released under the same, cc-by-sa license. 

Am I correct? 

In other words, is Attribution license a viral license? My understanding is 
that it is not, especially given the differences between cc-by and cc-by-sa 
license terms in section 4. But I thought I would double-check that with 
someone who has more knowledge or expertise.

Thank you for your help,

Tomo

_________________________________________________________________
会員登録は無料  充実した出品アイテムなら MSN オークション  
http://auction.msn.co.jp/