GSI Commerce, a leading e-commerce and marketing company based in King of Prussia, Pa., has purchased retargeting ad technology provider FetchBack for an undisclosed sum. The Tempe, Ariz.-based FetchBack creates industry-leading scalable technology that delivers targeted messages to online visitors after they’ve left a website, enabling marketers to recapture lost prospects.

The acquisition of FetchBack will complement GSI’s e-commerce business while expanding the reach of its marketing services into new markets. GSI offers fulfillment and customer-care services as well as website enablement. In addition to retargeting applications, FetchBack also provides an analytics platform that gives marketers some of the industry’s best insight into their online campaigns.

FetchBack clients include True Religion, Pingg, Abacus 24-7, Grand Canyon University and Aqua Superstore. The company has one of the largest client bases in the industry due in large part to its 95-percent monthly retention rate. FetchBack will operate as a wholly owned subsidiary of GSI’s Global Marketing Services division, which also includes sister companies TrueAction, Silverlign, GSI Media and e-Dialog.