Rollover ad tracking company Moat has secured a $12 million Series B round of funding led by Mayfield Fund. Previously the company raised $4.5M, including a $1.5M round led by Ron Conway’s SV Angel. The company offers an ad search program, which operates like a search engine for display ads for agencies and advertisers, as well as an analytics platform that goes beyond the dreaded clickthrough rate to track mouse-overs on an ad. That all operates on the premise that holding your mouse over something is an indictor of your attention. [Source: Moat]