Google is partnering with retailers to improve targeted ads

The war for advertising dollars between Google Inc. and Facebook Inc. may add a new front: email addresses. Google is in talks to allow advertisers to target ads in search results at their existing customers, according to people familiar with the matter. Google has suggested that advertisers hand over customer information such as email addresses, which Google would then use to target the ads, the people said. The move would follow a similar advertising service launched in 2012 by Facebook called “custom audiences,” which is helping the social network chip away at Google’s lead in digital advertising. Facebook reported ad revenue grew 65% to $11.5 billion in 2014 while Google’s advertising revenue grew 17% to $59.1 billion. The proposed ads highlight the increasingly sophisticated ways that Internet companies track users’ online and offline activities for marketing purposes. Such tactics might raise questions about how well customers understand what businesses do with personal information they volunteer to a website or through a store loyalty program.