A top Silicon Valley executive used high-tech trickery to pull off low-tech fraud -- printing his own bar codes to buy Legos at big discounts, then selling them on eBay, according to police.

Thomas Langenbach, who lives in a $2 million home in San Carlos, Calif., and is a top executive at German software giant SAP, allegedly plastered his homemade bar codes on Legos at the Cupertino Target. After taking them home, he sold them on eBay using the name “tomsbrickyard,” according to police.

"He sold 2,100 items in just over a year on eBay, and made $30,000."

- Police spokeswoman Liz Wylie

"In his house, we found hundreds of boxes of unopened Lego sets," Liz Wylie, a spokeswoman for the Mountain View police, told the Mercury News. "He sold 2,100 items in just over a year on eBay, and made $30,000.”

Police were tipped off by loss prevention officers at Target. They spotted him on security tape buying the interlocking plastic toys at unsanctioned discounts and put out fliers alerting clerks to the scam.

On May 8, a loss prevention officer on duty at the Mountain View Target recognized Langenbach and trailed him through the store, observing as he allegedly placed his own bar codes on several items. After he checked out, store security detained him until police arrived.

Armed with a search warrant, cops found a massive stockpile of Legos in Langenbach's house, as well as dozens of his homemade bar code stickers in his car.

Langenbach will be arraigned Tuesday on four felony counts of burglary in Santa Clara County court.

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