Amazon stops buying prized shopping ads on Google

Losing Amazon is a rare setback for Google's Shopping ads, which have been a massive financial success

Amazon has stopped buying a popular type of Google ad, according to people familiar with the decision. The move deepens the rift between the technology titans and signals Amazon's growing ambition in the digital advertising market.

The pullback affects highly coveted real estate at the top of Google search results, where retailers and e-commerce bid and pay handsomely to place colorful, image-rich ads that show up when consumers look online for running shoes, headphones and other products to buy.

Amazon began bidding for these slots, known as product listing ads, or PLAs, in late 2016. That pitted the e-commerce giant against retailers