While Britain's highest court said there was no clear winner in its ruling, trans groups said the decision would undermine their rights.

Trans women are not legally women under the Equality Act, the Supreme Court has ruled in a landmark judgment. Campaign group For Women Scotland (FWS) brought a series of challenges – including to the UK’s highest court – over the definition of “ woman ” in Scottish legislation mandating 50 per cent female representation on public boards.

The U.K. Supreme Court's decision adds to the mounting rollback of protections for trans people across the globe.