UPDATE: Flickr have now restored the option to delete their automatically generated tags
Flickr no longer allows users to easily remove the automatically generated tags that it adds to photos. Flickr has been using image recognition technology for a couple of years to automatically generate tags for users’ photos but didn’t make them visible until May 2015. As well as new photos, the computer generated tags had been added retrospectively to all previously uploaded photos. My own experience is that many of the tags are useless and some are totally wrong. See my earlier posting Flickr pulls out all the stops with automatic tagging.
User generated tags are in a grey box and Flickr’s automatic tags are in a white or light grey box. As the tags are used by Flickr when searching for images it is important that they are correct, and it explains why Flickr search results often contain irrelevant images.
Until now, both users’ and Flickr’s tags could be deleted. Hover over a tag and a cross would appear in the upper right hand corner enabling you to delete that tag. The cross no longer appears on Flickr generated tags so they cannot be deleted that way. There is a work around which is to manually add a tag that is identical to the one you want to remove and then delete the tag you have just added. This also deletes the corresponding Flickr tag.
Several people have commented that there is an option under Settings, Privacy and Permissions that enables you to hide auto tags. This does exactly what it says on the tin:”hides” the tags. It does not remove them so they will still be used by Flickr’s search.