Paranoid Bridgewater employees ventured into the woods to take some calls — until a rumor spread that the company was looking into installing listening devices in the trees, a new book says

• Some staff at Bridgewater Associates took personal calls in the woods so their employer couldn't listen in, a new book says.
• This stopped when a rumor claimed the firm might install devices in the trees, per "The Fund."
• Rob Copeland's new book describes apparent surveillance and employee paranoia at Bridgewater.

Some employees at Ray Dalio's investment-management firm Bridgewater Associates took non-work calls in the woods near their offices because they were worried about their employer listening in, according to a new book.