It’s been a central argument for the United Auto Workers union: If Detroit’s three automakers raised CEO pay by 40% over the past four years, workers should get similar raises.

UAW President Shawn Fain has repeatedly cited the figure, contrasting it with the 6% pay raises autoworkers have received since their last contract in 2019. He opened negotiations with a demand for a similar 40% wage increase over four years, along with the return of pensions and cost of living increases. The UAW has since lowered its demand to a 36% wage increase but the two sides remain far apart in contract talks, triggering a strike.

Fain’s focus on CEO pay is part of a growing trend of emboldened labor unions citing the wealth gap between workers and the top bosses to bolster demand for better pay and working conditions. In June, Netflix shareholders rejected executive pay packages in a nonbinding vote, just days after the Writers Guild of America wrote letters urging investors to vote against the pay proposals, saying it would be inappropriate amid Hollywood’s ongoing strike by writers. The WGA wrote similar letters targeting the executive pay at Comcast and NBCUniversal.