In a move that demonstrates media shops are eager to beef up their social credentials, Interpublic Group of Cos.' MediaBrands has acquired Seattle-based social-media-shop Spring Creek Group.

The move means Spring Creek will fall under the Mediabrands umbrella along with Interpublic media agencies Universal McCann and Initiative . The 30-person social-media shop lists as clients Microsoft, U.S. Bank, Best Buy and HTC, among others. It's a small firm; according to Inc.com, the five-year-old firm achieved $4.3 million in revenue in 2010. Mediabrands would not disclose its valuation. As part of the deal, Spring Creek will remain headquartered from its Seattle office and expand its presence to New York.

Asked what was behind the buy, Brendan Moorcroft, CEO of Mediabrands' Audience platform, which includes its agency trading desk Cadreon, explained that rather than just work with other Interpublic social-media resources, the group was looking for a social-media firm with analytics capabilities that could complement other media-planning and -buying operations. MediaBrands was attracted to the firm's ability to interpret data, intelligence and consumer behavior on social platforms, as well as its technology and financial services client portfolio, he said.

"We have the social assets within the IPG PR firms like Weber Shandwick, but they're not as focused around analytics and listening and finding optimization listening channels," Mr. Moorcroft said. "They're much more creative and communications-planning driven. Now we've got a deeper set of tools and skill sets that complement the work we've done."

Under the deal, Clay McDaniel, CEO of the Spring Creek Group, will move into the new position of managing partner of the Spring Creek Group and will report to Mr. Moorcroft. Mr. McDaniel said: "I decided to sell Spring Creek at this time because I knew it would provide the best opportunity for my team to build upon their expertise in social marketing by becoming an integrated part of larger digital programs."