Originally posted by GeeEmm Note, check your TOS for copyright issues, some sites claim copyright over uploaded images - I don't know if that has ever proved to be a problem, but if they make the claim I presume they have something in mind.
I'm not aware of any site claiming copyright over your photos if you upload them. Most of those claims stem from a misunderstanding of how it works. If you upload to something like Facebook because you want to share, Facebook is required to obtain your permission to repost your photos to be able to show it on other people's feed. They stipulate that you grant them that license for reposting your photos in their TOS as a blanket rule since that's presumably why you upload them in the first place. If they don't have that license granted to them, they could run afoul of copyright law when they show your photos to others. That even includes your friends going to your page to see them.
Other sites may require other licenses, and a common one is to use your photos in their own advertising. It's not a bad idea to check the TOS for possible conflicts of interest, but make sure you fully understand what it is stipulating (and hope the company understands and follows them as well), and not simply jumping to conclusions.