In a landmark and controversial move, the International Olympic Committee (IOC) has officially announced its decision to exclude Lia Thomas — the transgender swimmer who made global headlines for competing in women’s collegiate swimming — from participating in the 2025 Olympic Games.

The decision, confirmed in a formal statement released by the IOC this morning, cites updated eligibility guidelines that aim to “balance inclusivity with fairness and competitive integrity in elite women’s sports.”

According to the IOC, while they affirm their commitment to inclusivity and respect for athletes of all gender identities, the latest framework requires transgender women to demonstrate significantly reduced levels of testosterone for a sustained period of time and prove a “material competitive disadvantage has been mitigated.” After an internal review, the Committee concluded that Thomas does not meet the current criteria.

“The Olympic Games must ensure a level playing field,” the statement read. “This decision is not personal, but based on current scientific data and input from sport federations, medical experts, and athlete representatives.”

The ruling immediately sparked an outpouring of both praise and outrage.

Supporters of the decision argue that it is a necessary step to protect fairness in women’s sports, pointing to concerns that transgender women who went through male puberty retain physical advantages in speed, strength, and endurance. Critics, however, are calling the move discriminatory, accusing the IOC of caving to political pressure and undermining the rights of trans athletes.

Lia Thomas, who became the first openly transgender athlete to win an NCAA Division I swimming championship in 2022, has not yet issued a formal response, but sources close to her team say she is “deeply disappointed” and “evaluating her legal options.”

Athlete advocacy groups and LGBTQ+ organizations are already organizing responses, with several planning to challenge the IOC’s framework in international forums.

As the world gears up for the 2025 Games, this decision has reignited a global debate about gender identity, biology, fairness, and the future of inclusion in sport. With no easy answers and growing polarization, one thing is certain: the conversation around trans athletes and the Olympics is far from over.