every time someone copies a photo or document that you have uploaded, it shows up with their name and tree name in a box on right side of screen. You can see who and how many people have copied. Most of us post these documents hoping others will copy and find them useful! I love it when someone finds some rare and interesting thing I have dug out of some archive or country record place. But then I often look at the tree of those who copy my documents to see if they know anything about our common ancestor...I admit I am often disappointed when I see it is someone who has copied to their private tree. I could email and ask them who our common ancester is, but it rarely seems worth it.