The Thomson Corporation, parent of Westlaw, announced yesterday its first step into the B2B social networking market with its acquisition of Boston-based Contact Networks, a provider of relationship management technology for large law firms and other professional-services enterprises. From the announcement:

“ContactNet, the first and most powerful social networking application built specifically for corporate environments, automatically uncovers, aggregates and prioritizes a firm’s internal relationships with external business contacts. Now, determining ‘who knows whom’ is as simple as doing a Google-like search, with no data entry or ongoing database maintenance.”

Contact Networks’ customers include law firms Duane Morris and Mintz Levin.