Mimecast, an email security vendor, has announced its acquisition of cybersecurity firm Code42, which specializes in insider threat management. This acquisition will enhance Mimecast's Human Risk Management Platform by providing greater visibility into insider threats. The deal will also expand Mimecast's workforce by 175 employees. The financial terms of the acquisition have not been disclosed. This acquisition follows a challenging period for Code42, particularly after its founder, Matt Dornquast, left the company following a round of institutional funding.