Products like the Nest thermostat and Pixel phones — owned by Alphabet's Google — came up top in 91 percent of 25,000 related searches, according to analysis by the Journal and data firm SEMrush. The December analysis included terms like "laptops" and "speakers," but since then, after the WSJ shared its findings with Alphabet, some of the ads have disappeared, the Journal said.
Google told the Journal that it takes step to minimize conflict in the ad-bidding process, and that the results are based on "the ad's quality and the price Google is willing to pay." Google was second only to Facebook when it comes to 2016 display ad revenue worldwide, and is the leader in search ad spending.
In a statement to CNBC, a spokeswoman for Alphabet said:
We have consciously and carefully designed our marketing programs to not impact the ad auction. All our bids are excluded from the auction when determining the price paid by other advertisers, and we have strict rules and processes — set to tougher levels than our customers —to govern the use of our own ads products.
The data comes amid accusations from the European Commission that Google skews results to favor its comparison shopping service. At an event CNBC attended earlier this month, a Google executive said that rival Amazon was treated "just like any other retailer" if it bought ads for Google Shopping.