SUNNYVALE, CA-While dozens of companies in Silicon Valley continue to downsize, NetScreen Technologies Inc., which sells computer security products, has just signed one of the biggest real estate leases seen in the area this year.

NetScreen has signed a long-term sublease to occupy a 160,000-sf, two-story building at Ariba’s Sunnyvale headquarters. While the terms of the lease were not disclosed, the lease rate for the building falls between $1 and $1.80 per sf per month, triple net.

The building is part of a 715,000-sf development at Moffett Field owned by Jay Paul Co., which bought about 25 acres from Lockheed Martin to build the office campus. Ariba has a 12-year lease with the development firm and is subleasing the majority of the space.

To accommodate growth, NetScreen plans to relocate from its 70,000-sf of current space, which is spread between three Sunnyvale buildings, to the new Moffett Park building in February 2003.

NetScreen gained 50 employees recently when it acquired OneSecure Inc., a local intrusion-prevention company, and expects to add another 120 to 150 employees in the next year. Cushman & Wakefield brokers represented Ariba, while the Staubach Co. represented NetScreen.