It confirmed that the word 'sex' in the Equality Act of 2010 means biological sex — the physical sex someone is born with — and not the ‘gender’ listed on a Gender Recognition Certificate (GRC) means biological sex — the physical sex someone is born with — and not the ‘gender’ listed on a Gender Recognition Certificate (GRC) This decision clears up years of confusion about whether someone who has legally changed their ‘gender’ with a GRC should be treated as having changed sex in the eyes of the law Even if a pupil socially transitions or plans to change their legal “gender” when they’re older, this does not change their legal sex in the meantime.