Fiona Apple recently performed alongside Garbage‘s Shirley Manson at Girlschool LA, a festival including only female-identifying artists in its lineup. During the set, Apple wore a t-shirt that called out the Recording Academy’s Neil Portnow, who recently came under fire for saying women in the music industry should “step up” if they want more recognition. The shirt says “Kneel, Portnow.” Portnow has since said that he regrets the remark. On Thursday, a campaign of female music executives demanded Portnow’s resignation from the Recording Academy over the remark, saying “We step up every single day and have been doing so for a long time. The fact that you don’t realize this means it’s time for you to step down.” Watch a clip of the performance below.