I’ve gotten no response on the Google webmaster forums, but maybe somebody here knows.
Google image search insists on picking up images from other sites that members embed in comments. We don’t want to block users from inlining images, but we also don’t want to be showing up as the source for that image in Google Image Search.
We have
User-Agent: Googlebot-Image
Disallow: /
in robots.txt, which works to block Google Image Search from any images hosted on our site. But it does nothing for linked images.
There doesn’t appear to be any image equivalent of ‘rel=“nofollow”’ for images.
Any thoughts?