A Google spokeswoman declined to comment.
On two successive days this week, a pair of young men stood on a San Francisco street waiting for the special "Gbus" that ferries Google staffers to the Internet company's Mountain View headquarters 34 miles to the South.
Dressed casually in jeans and wearing black ski hats or hoods, the two men did not stand out from the dozens of other young tech workers waiting for the Google bus. On close inspection, each sported the curly wire of an earpiece, and one occasionally jotted notes down on a yellow stick-it pad.
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Instead of boarding the bus with everyone else, the two remained in the same spot, watching intently as a succession of Google's white corporate shuttles arrived for the morning pick-ups. In one instance, the bus driver waved to one of the men, who waved back.
Asked if they were security guards for Google buses, one of the men replied "Can I see your badge?" likely referring to the Google identification badges that employees of the company use to board the bus and enter buildings on the Google campus. The other man denied working as a security guard for Google, but declined to provide any information about his identity or his employer.