named Sanjay Jha, Qualcomm's chief operating officer, to head its money-losing mobile devices unit and become co-chief executive with Greg Brown.
The news sent Motorola shares up 9 percent. Investors said the hiring of Jha, a well-respected technology executive, gave the struggling company credibility and quelled doubts that it would go through with plans to split off the cell phone unit in 2009.
"For Motorola this is a coup," said Global Crown Capital analyst Pablo Perez-Fernandez. He said the 45-year-old Jha has a reputation for making people work hard.
"The appointment lends credibility to Motorola's plan to spin off mobile devices. I didn't think it was going to happen," said Perez-Fernandez.
Some investors had worried that Motorola, which has been looking for a new chief for its phone unit since early this year, was having trouble attracting strong candidates.
The company has struggled with market share losses to rivals such as Nokia and Samsung Electronics Co in the cell phone market due to a lack of advanced phones and a strong follow-up to its Razr phone.
Jha has worked at wireless chip supplier Qualcomm since 1994 in various roles, including president of its chip and software division.
Qualcomm said Len Lauer would be its new COO. Qualcomm shares fell more than 2 percent on news of Jha's departure. But Piper Jaffray analyst Michael Walkley said Jha's move could eventually lead to new business at Motorola for Qualcomm.
"It would be seen as a loss in terms of talent, but I think it's positive he went to a customer instead of another chip competitor," said Walkley.
Shares of Motorola, which plans to split off its mobile division as a separate company next year, rose 80 cents to $9.61 in morning trade on the New York Stock exchange.
Qualcomm shares were down $1.17 at $54.30 on Nasdaq.