Two Oregon high-school athletes filed a lawsuit on 9 July challenging state rules that allow transgender girls to compete in girls’ sports. The plaintiffs, who say they were forced to race against a transgender competitor at this year’s state championship meet, argue that Oregon’s policy violates Title IX and the U.S. Constitution’s equal-protection guarantees. They are seeking an injunction that would bar biologically male athletes from girls’ events while the case is litigated. In their filing, the teenagers cite last month’s widely followed social-media dispute between Olympic gymnast Simone Biles and former University of Kentucky swimmer Riley Gaines as a turning point that persuaded them to act. The exchange erupted after Biles defended transgender participation in sports and criticized Gaines’s stance. Amid the backlash, Biles apologised for a personal remark and deactivated her account on X on 23 June, saying the existing system fails to balance competitive equity with inclusion. Oregon is among a minority of U.S. states that permit transgender girls to compete in female divisions under guidelines set by the Oregon School Activities Association. The new lawsuit adds to a growing number of court challenges and legislative efforts nationwide over how to reconcile fairness in competition with the rights of transgender athletes. State education officials and the Oregon attorney general’s office have not yet commented on the case.