Chatham, N.J.—Theorem Inc., an online media operations and data services company, announced it has acquired Webpencil, an online creative ad design company. Terms of the deal were not disclosed. Webpencil co-founders David and Cheryl Rosowsky will remain with the company in their current roles. Theorem’s current capabilities include reporting, online ad and search operations services, rich media testing, trafficking and e-mail marketing campaign deployment. Las Vegas-based Webpencil specializes in online advertising creative and rich media across all platforms.