People who do not identify as male or female have achieved formal legal recognition in Australia for the first time, after the NSW Court of Appeal overturned a ruling that everyone must be listed as a man or a woman with the Registry of Births Deaths and Marriages.

In a landmark decision with major implications for thousands of intersex, androgynous and neuter people across the country, the court on Friday upheld an appeal by Sydney activist 'Norrie' against a decision by the Administrative Decisions Tribunal that people must be officially registered as 'M' or 'F'.

Long awaited victory: A specific sex identity shouldn't be forced on anyone, says Norrie. Credit:Dallas Kilponen

In 2010, Norrie, who identifies as neuter and uses only a first name, became the first in NSW to be neither man nor woman in the eyes of the NSW government when the 52-year-old Sydneysider was given the designation "sex not specified".

But four months later the registry wrote to Norrie, saying that the change was invalid and had been "issued in error".