License agreement on Art Station and New Grounds etc

[JosephCow]

I think it's a fair trade off personally. They give you a platform for your art, and in return they retain the rights to use the work on their platform. I don't know exactly how they are modifying images, but I don't think they would substantially change things for marketing or promotional purposes. I wonder if the license is ended if you remove you image from the site, or if they can still use it even after that?

But either way I think that's kind of the trade off with all of these sites. The alternative is just to have your own website.