Yahoo seems to be powering some search results with Google rather Bing, which has left some industry experts speculating about the future of the Yahoo’s ad serving partnerships.

Recently, search blog SEOBook noticed that in some browsers, Yahoo search was serving Bing ads, while in others, it seemed to be serving ads from Google. The change is probably a direct result of the loosening of Microsoft and Yahoo’s search contract, which the companies renegotiated last April. Under the terms of the new contract, only 51 percent of Yahoo’s search results are required to serve Bing ads. The other 49 percent are open Yahoo’s Gemini system or new partnerships. 

Yesterday, Yahoo confirmed to The New York Times that it is, in fact, testing ads with Google and hinted at more partnerships to come.

 “As we work to create the absolute best experiences for Yahoo users, from time to time, we run small tests with a variety of partners including search providers,” Yahoo said in a statement to the publication. “There is nothing further to share at this time.”