Prevent Google from listing hotlinked images for other sites

Question

I am hosting several domains on my server and hotlink images accross various domains.

However, I have found out that in Google searches, the images are listed as originating on the site where the image is displayed (but not hosted!). This can lead to various problems (like the owner of the site losing traffic). Space is an issue on some of the domains, so storing the images for every domain separately is no option.

Is there a way to instruct Google to display images only with the sites the images are actually stored on (and prevent that wit hthe others only hotlinking)?

Answer 1

Thanks! On further investigation, I also found the hint to add

<meta name="robots" content="noimageindex">

to the header of the web page - it is supposed to prevent the page used as the referring page according to a few sources. I'll see if that's sufficient and update my post if necessary.

Answer 2

To prevent the image being indexed via the site you are hotlinking from, instead of linking (hotlinking) directly to the source image you could perhaps call a script which reads and serves the appropriate image from the source site together with an X-Robots-Tag: noindex HTTP response header.

<img src="/get-image.php?file=my-image-hosted-elsewhere.jpg" alt="">