Shanghai-based software company Zhizhen Network Technology, which sued Apple four years ago over a voice recognition patent for the iPhone Siri “personal assistant”, plans to expand into the US in 2017 with ambitions of becoming a global leader in artificial intelligence. It will set up offices in Hong Kong and Silicon Valley to develop software to cater to local clients, a fresh sign that Chinese technology firms are speeding up their “go-global” drive to take on big-names such as Microsoft and Amazon for world markets.