Data storage giant NetApp, buoyed by surging revenue, is embarking on yet another major expansion at its Research Triangle Park campus that is expected to add 460 high-paying jobs over the next four years.

The California-based Fortune 500 company plans to invest more than $75 million to expand its RTP research-and-development operations, where it now employs 1,450 workers.

NetApp could receive $11.8 million in state incentives if it meets its hiring and investment goals. It’s the third time the state has offered the company incentives to expand locally. Commerce Department spokesman Tim Crowley said that to date NetApp has met all the targets for hiring and retaining employees spelled out in the incentive packages it received in 2004 and 2007, when it pledged to add 175 workers and 646 workers, respectively.

NetApp laid off about 600 employees worldwide in February 2009, but over the past two years it has been hiring aggressively in the Triangle and elsewhere to keep pace with its growing revenue. The company, which overall employs more than 12,000 employees, generated $6.23 billion in revenue for the fiscal year that ended April 27, up 22 percent from a year earlier.

NetApp expects the new jobs to pay an average annual salary of $103,043, well above the Wake County average of $45,396, according to the Commerce Department. NetApp’s campus is on the Wake County side of RTP.

“I’m doing cartwheels over here,” said Wake County Manager David Cooke.

The Wake County commissioners haven’t approved an incentives package for NetApp. But if they adhere to the county’s policy, its incentive would amount to 2.25 percent of the company’s new investment after meeting its targets. That would amount to $1.7 million if NetApp invests $75 million, although Cooke expects the company will invest considerably more than that based on its track record.

NetApp already is the county’s 12th-largest taxpayer, Cooke said.

Ken Atkins, executive director of Wake County Economic Development, said the county has made recruiting information technology and software companies a priority and NetApp’s announcement “underscores what a good area this is for these types of companies.”

Gov. Bev Perdue announced the expansion at a news conference on NetApp’s RTP campus Monday afternoon, just minutes after the state’s Economic Investment Committee approved the incentives.

NetApp chose RTP over Wichita, Kan., where it also has a facility.

Denise Cox, NetApp’s senior vice president of global support, said the company’s success at attracting highly qualified employees in RTP, combined with a low attrition rate, was a key factor in the company’s decision.

“People stay and grow with us,” said Cox, who noted that the company had just 50 local employees in 2003.

Although the brunt of NetApp’s latest expansion will be in research and development, the company will add to its tech support staff as well. Today NetApp’s RTP campus is home to about 500 tech support workers, making it the company’s largest tech support site.

Having R&D and tech support in close proximity helps the company provide a better product because the tech support staff can highlight areas that can be improved based on their work with customers, Cox said.

NetApp fully occupies two buildings at its RTP campus and will expand its presence in a third building.

NetApp also has plenty of room for expansion beyond those buildings.

“I will tell you that we own about 70 acres across the street as well,” Cox said.

Staff writer David Bracken contributed to this report.

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