Most reputable social media companies like Facebook, Twitter and LinkedIn require users to agree to a terms of service agreement before registering an account.
While these contracts generally don't give ownership of published content to the social media companies, the agreement does usually secure the companies a broad license to use anything users post to their platforms.
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Most social sites have similar language. This enables the sites to have an expansive right to use all posted or shared content without being liable to you, Sell said.
While Facebook does not currently give third party applications or ad networks the right to use a user's name or picture in ads, it does reserve the right to use a user's name and profile picture in social ads on its own platform.
For example, if a user "likes" a brand on Facebook, the person's name and picture may show up alongside that brand's advertising message in a friend's newsfeed, but only if the user has opted to share their "likes" with friends.