Starbucks baristas went on strike at several stores in Chicago, Seattle and Los Angeles on Friday, with their union warning the walkouts could spread to hundreds of cafes by Christmas Eve if the coffee giant does not meet workers’ demands at the bargaining table.

Workers at some Starbucks stores started a five-day strike Friday in three U.S. cities, including Chicago, to protest lack of progress in contract negotiations with the company. S

As Novo Nordisk and Eli Lilly expand sales of their popular diabetes and weight-loss drugs, cheaper copies of their patented remedies are winning approval from some regulators overseas, posing a threat to the pharma giants' prices and market share.