In a landmark decision, the Court of Arbitration for Sport (CAS) has rejected a challenge from transgender swimmer Lia Thomas to overturn a policy that prevents her from competing in women’s races at elite competitions. The CAS panel determined that for the time being, Thomas is not eligible to compete in elite events organized by both World Aquatics and USA Swimming.

Thomas, who made history as the first openly transgender athlete to win an NCAA championship at the Division I level, argued that the gender inclusion policy of World Aquatics was discriminatory as it effectively barred transgender competitors from participating in men’s or women’s races at high-profile events such as the Olympic Games or world championships. The federation had proposed creating “open category” races for transgender athletes in addition to categories for men and women.

World Aquatics welcomed the CAS ruling, stating that it represents a significant step forward in efforts to ensure fairness and equal opportunities for athletes of all genders. The federation reiterated its commitment to promoting inclusivity in aquatic sports and continuously reviewing its policies to align with these values.

An attorney representing Thomas did not immediately respond when asked for comment on the CAS decision.