Change In Intellectual Property Law
Last month the law in the UK changed to allow copyrighted works to be used without the owners consent if they are "orphaned" and the owner cannot be found. The majority of images on the Internet are (or could be) orphaned as the image or (EXIF) information in the file does not contain the owners details. Unfortunately any images that that do contain the owners details can easily be stripped of the information.
For the first time orphan works will be licensed for use; these are copyrighted works for which the owner of the copyright is unknown or can't be found. UK government website
As a result of this new law any photograph on the web could be used or sold without the owners permission.
The only way to stop this is to pay to register the work with an approved registry.