• by Laurie Sullivan , Staff Writer @lauriesullivan, September 10, 2014

Google made it possible for brands to extend their Shopping Campaigns beyond google.com and into the Google Search Network that includes retailers like Walmart.com as part of the tech company's AdSense for Shopping program. The retailers need to opt-in to the program, allowing partner ads to serve up.

The move enables product listing ads (PLAs) from Google partner sites to run alongside contextually relevant results at retailers, driven by the consumer's search, the product category, and the product name across Google's search network. Retailers must opt in to push campaigns directly into Google's ecommerce partners' search results on retail sites and other third-party sites.

Someone searching for a barbecue grill on Walmart.com may now also see additional options from third-party merchants during the actual search through sponsored product ads that also appear in the list. In the case of Walmart, the ads appear down the left rail.

Amazon reportedly will drop Google AdSense from its network of sites by year's end and roll out its own AdWords competitor, supported by a treasure trove of data from sites like Zappos, Pets.com, and Woot, among others. This would allow Amazon to target consumers with ads and recommendations based on purchases, not just searches.

Similar to text ads, opting to run the PLAs on search partner sites will not affect the brand's quality score on google.com -- something to consider when planning campaigns, per Jesse Adkins, product manager for Google Search Ads. Today, AdSense for Shopping is limited to a small set of retail and commerce publishers.

Searching for a Disney throw on Walmart.com returned options at Wayfair, SportsKids, and Epic Sports alongside those at the retailer. Not all items searched on serve up products. Xbox returned zero sponsored ads, for instance.