SAN JOSE (CBS SF) — The ringleader of a $37 million computer chip heist in Fremont in 2011 that is believed to be the largest such heist in Silicon Valley history pleaded no contest Wednesday to four robbery counts in an agreement that calls for him to get an 18-year state prison term.

Faustino Adona, 46, of San Jose, entered his plea in Alameda County Superior Court shortly before he was set to go on trial and will be formally sentenced by Presiding Judge Morris Jacobson on Nov. 27.

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Adona was one of 16 men who invaded Unigen Corp., a silicon and modules design and manufacturing company, at 45388 Warm Springs Road in Fremont at about 8:45 a.m. on Feb. 27, 2011, a Sunday, California Deputy Attorney General Ralph Sivilla said.

Authorities said the men, who were from San Jose and Union City, wore masks and dark clothes and were armed with handguns and rifle. They bound five Unigen employees at gunpoint and forced them into a backroom.

The suspects then loaded nearly 2 million flash memory chips onto a large truck and drove away at 9:11 a.m. that day.

Authorities later determined that the heist was an inside job because two of the suspects worked at Unigen, which is now based in Union City.

As part of its investigation into the heist, Fremont police enlisted the help of the Rapid Enforcement Allied Computer Team, or REACT, a high-tech crimes unit of the Santa Clara County District Attorney’s Office.

The investigation quickly led to the recovery of nearly 1.5 million of the stolen chips locally and in Asia.

Two of the suspects remain at large but most of the suspects were arrested within a few months of the large robbery, Sivilla said.

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Adona was arrested in the Philippines and it took a long time to get him extradited to the U.S. so he could be prosecuted here.

He is the last of the 14 suspects who’ve been arrested to resolve his case, according to Sivilla.

The men were charged with multiple counts of armed robbery and kidnapping for robbery.

In exchange for Adona’s no contest plea to four counts of robbery, prosecutors agreed to dismiss the kidnapping charges he faced.

Sivilla said most of the other defendants were sentenced to state prison terms ranging from 15 to 17 years.

He said the defendants apparently planned to sell the stolen computer chips to foreign tech companies.

Jacobson said the 14 defendants cumulatively are ordered to pay $782,600 in restitution fines, since that’s the value of the chips that never were recovered.

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