More than 1,000 Starbucks baristas at 75 US stores have gone on strike since Sunday to protest a new company dress code, a union representing the coffee giant’s workers said Wednesday.

“We’ll establish normal strike teams for pickets of three shifts a day, 24 hours, seven days a week until we get some resolution,” Shafar said. Negotiations began in March. The union’s ...

The union says its current contract demands would cost only $4 million more per year compared to management’s previous contract offer that was rejected by members. A strike, it added ...