As Amazon eats into search ad revenue, Google is fighting back. According to some studies, Amazon had overtaken Google for product searches in the U.S.  by June 2018, with 54% beginning on Amazon versus 46% on Google. Brand dollars mirror the shift. In 2018, WPP reportedly tripled ad spend on Amazon search ads, with 75% of that budget apparently pulled from Google.

Google says it is reacting to changing consumer habits not competition, but in truth it knows purchase trumps purchase intent. Google’s stock plummeted while Amazon’s climbed on their last round of quarterlies. Whether Google can start to smoothly shift more product via partners and third parties without investing in distribution and remaining unfettered by additional cost will influence its success in curbing Amazon's march, or lack thereof. But the upshot of increased competition is positive for marketers as each platform must make its wares more attractive. Meanwhile, new formats create a fresh set of opportunities for advertising's supply chain to advise, create and execute.