LONDON—Integrated communications agency Cicero Group has acquired Yatterbox, a social media monitoring service that identifies and tracks key influencers and commentators. The deal, which values Yatterbox at a significant six-figure sum, will see Cicero take a significant position in the social media monitoring market in the PR and communications space.

Yatterbox now includes more than 4,000 influencers drawn from the media, blogosphere, politics, think tanks, government departments and other key individuals who impact the reputations of organisations on a daily basis. Cicero plans to rapidly expand the platform to 25,000 people, to include every UK-based journalist, politician and important influencer by the end of the year.

Access to Yatterbox—across both online and mobile platforms—will be free while the service is enhanced further, and Cicero chief executive Jeremy Swan says: "The intelligence that can be gained through social media, whether for a FTSE-100 company or a week-old start-up, is only just being realised.”