Walmart buys ad tech startup

NEW YORK - Walmart says it's buying San Francisco-based ad tech startup Polymorph Labs as it looks to better compete with rival online juggernaut Amazon in targeting shoppers online.

The world's largest retailer has been quietly building its own advertising business with a unit called Walmart Media Group, though that business is still smaller than Amazon's.

http://www.startribune.com/walmart-buys-ad-tech-startup/508448042/