We've recently been finding some ads appearing on Yahoo and Bing without a Display URL. We first noticed this on Yahoo, where the ads were simply composed of a headline and description text (without any space for a Display URL to appear). In some more recent monitoring, the examples we've found on Bing have always included a lone dot in the Display URL field. In the Bing example on the right, you can see this dot followed a gap where the Display URL would normally be.
Initially, this seemed like a test that Yahoo was running. Yahoo has often experimented with different ad formats in the past, so this wouldn't be a shock at all. But how would brands be affected by an experiment like this? One potential issue would be that brands could no longer identify themselves in their own ads. Without the Display URL for proof, competing advertisers could look very similar—if not identical. If this experiment picked up momentum, what would brands do to distinguish their ads from the crowd?
Fortunately, this doesn't seem like something that Yahoo or Bing is actually considering. The Bing examples, with a single dot instead of a Display URL, indicate that this is most likely a minor technical issue. Of course, in the short term that means that some SERPS will still include these types of ads. But overall these ads are quite rare, and in the long run we don't expect to continue seeing them. This isn't a significant cause for concern at this time. And if something changes, we'll be keeping an eye out and let you know.