Barbara Hess has written an interesting blog post (original in German, linked version automatically translated by Google) on the subject of image usage rights; her approach, with which I agree, is to ensure that clients get the maximum use out of photos they receive, and understanding and considerate license terms. A part of this is an important mention of how a client adding photos to Facebook may, through their terms and conditions, may breach the usage rights to which they’ve agreed.
We post, share and “like” photos on all sorts of platforms. This isn’t actually allowed in many cases: according to Facebook’s terms and conditions, they receive the usage rights. If you post a photograph where the copyright belongs to someone else, you are passing on usage rights which you don’t possess. And it gets even more complicated. t3n has produced a clear overview* of what is actually allowed on Facebook.
*Linked page in German