DURHAM - Motricity will lay off 250 workers and move its world headquarters from Durham to Bellevue, Wash., company officials announced to employees this morning.

The fast-growing technology company will likely vacate its headquarters building at the American Tobacco Complex in downtown Durham within nine months, dealing a blow to that city's efforts to recruit high-tech companies.

The restructuring comes after Motricity raised several hundred million dollars from investors in recent years, including from billionaire financier Carl Icahn. In December, the company put that money to work by purchasing the former mobile services unit of Bellevue-based InfoSpace for $135 million.

That company is now taking the lead in reshaping the combined operation, in terms of the technology used to serve customers, the headquarters and the work force.

The majority of the layoffs are Motricity employees, not former InfoSpace workers, said Motricity CEO Ryan Wuerch, who will stay on as chairman of the board and chief executive.

Wuerch late Monday lamented leaving Durham and cutting the majority of the company's local work force.

"This was one of the hardest parts of the decision," he said. But he fully supports both moves as the best means to success for Motricity's investors.

The rationale is that Bellevue is a much better location for Motricity to do business than Durham. The company, which runs the software that allows people to download media to their cell phones, will benefit from the Seattle area's larger pool of mobile-content professionals, company officials said.

Further, Motricity's largest customers, wireless carriers AT&T and T-Mobile, have major operations in that area. So do strategic partners such as Microsoft, Google and others.

Laid-off workers will receive 60 days' notice and severance packages based on seniority.