The European Court of Human Rights has ruled in favour of double 800m Olympic champion Caster Semenya in a case related to testosterone levels in female athletes.
The South African athlete was born with differences of sexual development (DSD) and isn't allowed to compete in any track events without taking testosterone-reducing drugs.
Semenya has been in a long-running dispute with World Athletics who require her to have hormone treatment.
She has twice failed in legal battles to overturn the decision however the case at the European Court of Human Rights was not against sporting bodies or rules - but specifically against the government of Switzerland for not protecting Semenya's rights and dates back to a Swiss Supreme Court ruling three years ago.
The ECHR found the Swiss government did not protect Semenya from being discriminated against when its Supreme Court refused to overturn a decision by the Court of Arbitration for Sport (which upheld the World Athletics rules).
Cas has previously ruled that testosterone rules for athletes like Semenya, were discriminatory - but that the discrimination was "necessary and reasonable to protect "the integrity of female athletics".
While the judgement would appear to vindicate Semenya's long-held view that she has suffered discrimination, it's uncertain if or how the court's decision will impact the current restrictions on DSD athletes.
World Athletics has doubled down on its position in its efforts to protect fair competition in the female category, and is also keen for the Swiss courts to challenge the ECHR verdict.
There is a three-month window to lodge an appeal.
In terms of competing - if that's what she wants - that leaves Semenya in a similar position to where she was before the ECHR ruling, unless she takes medication to suppress her testosterone or World Athletics is forced to change its position on DSD athletes, and it's not clear how that could happen.
As it stands, she still cannot compete in female track events.
An ECHR statement said Semenya "had not been afforded sufficient institutional and procedural safeguards in Switzerland" to allow her to "have her complaints examined effectively, especially since her complaints concerned substantiated and credible claims of discrimination as a result of her increased testosterone level caused by differences of sex development."
The EHCR ruling suggests that the World Athletics' DSD regulations were "a source of discrimination" for Semenya "by the manner in which they were exercised and by their effects", and the regulations were "incompatible with the European Convention on Human Rights".
The decision, made by a panel of seven people at the ECHR, was split 4-3 in favour of Semenya and may allow her to challenge the Swiss Supreme Court or Cas rulings.
World Athletics described the ECHR chamber as "deeply divided" and said it will ask the Swiss government to refer the case to the ECHR Grand Chamber for a "final and definitive decision".
World Athletics said: "We remain of the view that the DSD regulations are a necessary, reasonable and proportionate means of protecting fair competition in the female category as the Court of Arbitration for Sport and Swiss Federal Tribunal both found, after a detailed and expert assessment of the evidence.
"We will liaise with the Swiss government on the next steps. In the meantime, the current DSD regulations, approved by the World Athletics Council in March 2023, will remain in place."
A statement from Semenya's lawyers said: "Caster has never given up her fight to be allowed to compete and run free. Today's judgment is testament to her resilience and courage. This important personal win for her is also a wider victory for elite athletes around the world.
"It means that sporting governance bodies around the world must finally recognise that human rights law and norms apply to the athletes they regulate."
A statement from Athletics South Africa said the ruling "vindicated" its belief that the existing DSD rules were "ill-conceived" - and that it would seek legal advice about the consequences for Semenya's potential future participation in athletics.
Background on DSD rules
Under regulations introduced in 2018, athletes with DSD were only allowed to compete in track events between 400m and the mile if they reduced their testosterone levels.
However, in March World Athletics ruled that DSD athletes must now have hormone-suppressing treatment for six months before being eligible to compete in all events.
Semenya ran in the 5,000m at last year's World Championships in Oregon but failed to qualify for the final.
She has argued that taking testosterone-reducing medication could endanger her health and that the ruling denied her and other athletes with DSD the right to rely on their natural abilities.
Because of the ruling, she could not defend her 800m title at the Tokyo Olympics, which took place a year later than planned in 2021.
Semenya, who has always been legally identified as female, has said she should be able to compete in women's events even if her testosterone levels are higher than her competitors.
In 2019 she told BBC Sport she had been "crucified" but will "never stop fighting" against the regulations brought in by World Athletics than known as the IAAF.
*This story was first published by the BBC