Other than a skeleton force of fewer than 100 people, Motricity is abandoning the Bull City and shedding 250 workers.

Most of those being laid off in a restructuring announced Tuesday are part of the 350-employee work force the provider of mobile content infrastructure services has at its headquarters in Durham.

Motricity is moving its headquarters to Bellevue, Wash., and other than a few key personnel, Chairman and Chief Executive Officer Ryan Wuerch won’t have many familiar faces with him. Wuerch is among those select Motricity employees who will relocate to the West Coast, according to a company spokesman,

A much smaller operation with fewer than 100 employees will remain based in Durham, the spokesperson said. However, whether Motricity will remain in its recently opened headquarters in the American Tobacco complex is not known. The company will either move to a smaller location or sublet space, according to the spokesperson.

Motricity has strong roots in the Triangle, dating to 1999 when high school students Jud Bowman and Taylor Brockman launched a company called Pinpoint. The firm later merged with PowerbyHand, a Tennessee-based firm that Wuerch ran. Wuerch decided to base the combined company in Durham and renamed it Motricity.

The relocation will position Motricity management and what’s left of the 650-employee company closer to the InfoSpace mobile information business unit Motricity acquired last year. Two of Motricity’s largest clients – AT&T and T-Mobile – also have large operations in that area, the company noted.

Motricity also believes the Bellevue location will help it to recruit software engineers who are more familiar with wireless operations, the Motricity spokesperson added.

“Because the mobile industry moves so fast, we can’t afford long times to ramp up and train,” the spokesperson said. “Being in the business we are in, it will be easier to find mobile engineers [in Bellevue].”

Steve Elfman, Motricity’s No. 2 executive as president and chief operating officer, is based in Bellevue. He ran the InfoSpace unit that Motricity acquired for $135 million. The deal came after Motricity raised $185 million in additional venture funding from billionaire investor Carl Ichan.

The restructuring news was announced to employees at an all-hands meeting at 9 a.m. on Tuesday. Wuerch broke the news in a session that lasted about 30 minutes. Employees being laid off will receive a 60-day notice and severance based on seniority as well as vacation time, a spokesperson said.

News of the shakeup was not unexpected, however. On Feb. 22, WRAL.com and WRAL Local Tech Wire first reported the news about massive layoffs and the likelihood the headquarters would move.

Motricity will discard or sell off part of its operations that focus more on content and put more emphasis on applications needed by mobile-service providers, Wuerch told employees.

“Historically, Motricity has been involved in several areas of mobile content,” Wuerch said in a statement. “The InfoSpace acquisition gave us the opportunity to refine the focus of our organization on areas where we have the strongest market position and are seeing the fastest growth today.

“Moving forward, our strategy will be aligned with our core business of providing mobile content infrastructure services – enabling consumers to discover content inside and outside the walled garden,” he added. “These services include powering portals, storefronts, managed Web and search for mobile operators along with messaging gateway services for all customers needing a mobile solution.”

Pocketgear.com, an e-commerce storefront operated by Motricity, will be divested, Motricity said. In December, it sold off eReader.com, a provider of e-books.

Motricity also has decided to utilize proprietary technology from InfoSpace called mCore rather than its own software known as Fuel. The technology enables mobile service providers to deliver content to cellular phone users.

“The steps we’re taking to quickly integrate the two companies will position us very well for accelerated growth, while offering greater discipline and a more focused approach for our customers,” Wuerch said. “While these decisions are always tough, we’re doing what is necessary to position Motricity for long-term and profitable growth.”

Motricity also has offices in Los Angeles, the United Kingdom, the Netherlands and Germany.