Step 1: You upload content to some site, with the intent they'll display it to other people. Step 2: They display it to other people. Step 3: If they didn't h

Step 1: You upload content to some site, with the intent they'll display it to other people. Step 2: They display it to other people. Step 3: If they didn't have a clause like this, you sue for copyright infringement. Basically, in order to do anything useful at all -- even to store the content, assuming a distributed store that makes multiple copies -- they need an actual, honest-to-god copyright license from you, the creator of the content. "But we figured he wanted us to because he uploaded it" is not a license and will not hold up in court. Granting a license does not transfer ownership; it is simply a set of permissions. People who really and truly ought to know better continue to post scary and idiotic posts claiming that it's a change of ownership though. You shouldn't listen to those people.