The Gaelic people of Scotland historically had three genders. It exists in both folklore (i.e: changelings) and in the Gàidhlig language with an archaic third grammatical gender. This decision is a disgrace to modern citizens and the history of the colonized within the UK. Fix your hearts.
The UK Supreme Court has unanimously decided that the definition of sex under the Equality Act 2010 refers solely to biological sex, and does not include people with a Gender Recognition Certificate.