What I meant was, that if someone distributes their changes outside their organization, they must also distribute (or make available) the source to those they distribute to. They must also license the changes under the GPL. So, I as the author could aquire the changes either from the person making the changes or the downstream. Another way to look at is that I derive some "gain" by forcing you to distribute / make available the changes to anyone to whom you distribute the modified program.
jeff smith
