Thomas Earnest, previously Matterhorn Legal, joins Mintz as member-corporate practice, for clients including technology, videogaming and digital media ... Sivers Semiconductors appoints Vickram Vathulya, ex-Nuvotronics, as president-CEO, succeeding Anders Storm, effective Aug. 19... Data solutions company Somos appoints Kayla Gardner, ex-Google, as director-public policy and government affairs and expands role of Joel Bernstein to vice president-head-U.S. public policy and government relations ... Sophos hires Teresa Anania, ex-Zendesk, as chief customer officer ... Cybersecurity company Blumira hires Marc Davis, previously Davmar Consulting, as channel development leader.