The group said a “full and final settlement” had now been agreed with ministers after years of litigation. In a statement issued yesterday, it confirmed receipt of £392,500 covering expenses in the Court of Session and the Supreme Court.

For Women Scotland estimates that, once ministers’ own legal fees are included, more than £550,000 of public money has been spent on the cases.

The group said the funds would support an ongoing judicial review of Scottish prison guidance and any further legal action to ensure compliance with the ruling.

Of the total recovered, £150,000 relates to proceedings in the Court of Session and £242,500 to the Supreme Court appeal. The sums were held in a deposit account by its solicitors, Balfour and Manson.

The litigation stemmed from statutory guidance under the Gender Representation on Public Boards (Scotland) Act 2017, which sought to ensure that at least 50 per cent of non-executive members of public boards were women. The guidance included in the definition of woman someone who had “taken the decision to undergo a process for the purpose of becoming female”, without requiring them to “dress, look or behave in any particular way”.

For Women Scotland argued that ministers had exceeded their powers by adopting a definition that conflicted with the Equality Act, which is reserved legislation. After a series of appeals, the Supreme Court ruled unanimously in April that a gender recognition certificate does not change a person’s sex for the purposes of the Equality Act, and that “woman”, “man” and “sex” refer to biological sex.

The Scottish government has since revised guidance, including on single-sex spaces in schools. However, disagreement continues over prison policy, with ministers resisting a blanket ban on trans prisoners in women’s jails.

For Women Scotland said: “We are eternally grateful for the overwhelming public support that enabled us to successfully challenge the Scottish government’s unlawful actions and to clarify that ‘woman’, ‘man’ and ‘sex’ have always taken their biological meaning in the Equality Act 2010.”