Sandberg’s Advertising Empire Leaves a Complicated Legacy

Sheryl Sandberg once remarked that she felt she was put on earth to scale organizations — and during her career as one of the most powerful executives in Silicon Valley, she plowed straight toward that grandiose vision. As an advertising head at Google in the mid-2000s, and as chief operating officer at Facebook for 14 years until her resignation Wednesday, Sandberg oversaw a period during which the internet services ballooned to colossal sizes, fed by a seemingly endless fountain of advertising revenue.

Though Sandberg may get most of her name recognition from “Lean In” — her 2013 blockbuster book encouraging women to take charge in the workplace — her most significant and complicated legacy may be the tech industry’s reliance on personalized advertising, which created both profits and complex nightmares at immense scale.