Siris Capital Group, a private equity firm, completed the merger with Polycom, a company helping organizations achieve new levels of teamwork, efficiency and productivity by unleashing the power of human collaboration, in a $2bn deal. The previously announced $1.6 billion cash and stock merger agreement with Canadian telecommunications company Mitel Networks was topped by Siris and accordingly terminated.  "We are very excited for the opportunity to partner with Polycom and its leadership team, as the company fits well with Siris’ investment focus on mission-critical telecommunications businesses," Dan Moloney, Siris Capital Group executive partner.