I have just been on this website: http://www.articlesbyte.com/Article/Web-Page-Design-Instruction---The-Vital-Role-of-Colors/71299. I noticed some links below a headline called "Related Links" which were actually a Google 468x60 ad without the 'Ads by Google' or urls! I looked at the source code and can't figure out how this happened. I don't think there is any trickery going on here so is this a Google mistake or what?
Edit: Good catch... i copy pasted the adsense code in a seperate html file and saw no ads by google... so thought it was legit
Here's another naughty site that's been spamming up my referers log and has AdSense in an IFRAME to hide the "Ads by Google". http://www.top-ogloszenia.com/ If anyone knows Polish, then perhaps they can report them.
You don't have to speak Polish to report them, just click on the Ads by Google part of the adbox and scroll down to the bottom of the page.
hows that possible i have not found any thing in google code but its possible that google does not offer ads by google tag with premium publishers!
The thing is I actually clicked on one of the links not realising it was a Google ad because it looked like just like a link to another topic. Pure subterfuge in my book and totally against Googles TOS.