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According to a source, a Google engineer recently ended a counteroffer war with Facebook by accepting $6 million worth of Google stock to keep her job there. Apparently she was not in a senior role at Google, but part of what made her so coveted was the fact she’s a female engineer. And this was Google’s second counteroffer after she had already told them she was going to Facebook.
At this point, Facebook (narrowly) has fewer employees than Google has job openings.