Nuance Communications (NUAN), which develops automated voice technology, is climbing after billionaire investor Carl Icahn announced last night that he had obtained a 9.27% stake in the company. Nuance's solutions are able to understand human voices and are used by businesses to carry out a variety of tasks and services. ANALYST REACTION: In a note to clients earlier today, Wells Fargo analyst Gray Powell wrote that Icahn's investment should be positive for Nuance's stock. Investors will expect Icahn, who is known for his activism, to pressure Nuance to take steps that will increase the returns generated by its businesses, Powell believes. The analyst, however, thinks that the company is currently facing several obstacles and he expects most of its fiscal 2013 growth to occur in the second half of the fiscal year. Powell maintained a Market Perform rating on the shares. TODAY'S PRICE ACTION: In early trading, Nuance jumped $1.40, or 7%, to $21.60.