Ok...I'll have to "widget" this story to keep within the TOS.
A few months ago a widget was in the news. I noticed a huge spike in our numbers and upon investigation saw that one of our original photos of the widget was on the first page of image results.
Suddenly the numbers dropped. Apparently quite a few sites liked our widget photo, stole it and with the new crawling speed of Google Images, tossed us into the results basement within a few days.
We went after the various sites and one by one they removed our widget photo from their posts and I made sure they deleted the image from their servers as well.
However the thumbnails for the infringing sites are still in Google Image search. When you click on the "See full size image" link, you get a 404. Yet Image Search is clinging on to the thumbnails like a drowning man clings a floating device. To add insult to injury, one of the 404'd thumbnails is even in the image samples on the Web Search side driving even more impressions to a site that no longer has the photo.
How long does Google hold onto 404'd images? Is there any recourse?
Funnily enough, I caught another site using the widget photo a day ago. They promptly deleted it. Today, that thumbnail appeared in the web search image samples even though it was just 404'd and never appeared there from that site before.