Drawbridge, headquartered in San Mateo, California, which is a cross-screen mobile ad targeting company, has raised $14million Series B funding led by new investor Northgate Capital. Previous investors Kleiner Perkins Caufield and Byers and Sequoia Capital also formed a prominent part of the funding. The company has now taken its total funding to $20.5 million. Drawbridge previously raised Series A funding of $6.5 million in May 2012.

Drawbridge intends to use the funds to increase sales and marketing capabilities on its desktop-to-mobile retargeting and audience targeting products. The funds will also be used towards product development efforts and the company will continue to work on accurate conversion tracking and post-conversion event optimization.

Founded by Kamakshi Sivaramakrishnan in November 2010, Drawbridge identifies cases where multiple devices are being used by single users so that mobile advertisements can be targeted using richer data that is collected from cookies on the desktop web. The company profiles web users by aggregating the billions of ad requests made through ad networks daily and organizing the data based upon time, IP address, device type, browser type and device ID. Through statistical analysis and pattern recognition, Drawbridge says it can track how individual user traverses the web on his or her smartphone, tablet, laptop and PC.

Over time, Drawbridge gets more accurate in connecting a person on mobile to the same person on the desktop. The company has matched more than 200 million mobile devices to desktop bookies. It needs about 15 to 20 observations of a user over two to three weeks to match someone. In terms of accuracy, the company can match up to 60 to 70 percent accuracy across devices. Drawbridge has matched 450 million devices and is growing by four million every day. The company has attracted clients in travel, eCommerce, retail, and media verticals.