Why CC-BY and CC-BY-SA licenses are DFSG-free?

[Bagas Sanjaya <bagasdotme@gmail.com>]

Hello,

I'd like to know why CC-BY and CC-BY-SA licenses are DFSG-free, and not 
NC and ND variant ones? I had tried to find the explanation on this 
mailing list, but seems like there is nothing found.

Cheers, Bagas
--
An old man doll... just what I always wanted! - Clara