Google will let companies target ads using your email address

Google will soon let advertisers tap into one of the most lucrative types of ad targeting: email addresses. The search giant is rolling out a new tool called Customer Match, which lets advertisers use a list of email addresses to target specific users across Google services. To be targeted through this technique, you only need to be logged into your Google account and have given your email address to a retailer, perhaps by buying something from their website or giving it out to sign up for a loyalty program. Google will also be compiling lists with general customer habits like YouTube viewing and Google search histories to target ads with.

By tapping into email addresses, as both Facebook and Twitter have already long been doing with their own respective products, Google can take higher cuts of the more costly and better targeted ads being served even from within the Gmail and YouTube apps on mobile devices. Google calls Customer Match a "privacy-safe" product, but that may not quell the concern of users who feel that advertisers are getting even more specific with their ad targeting.