@TheLoneRager
one of the claims was that they could be 'outed' to their employer via their NI number. I think this was because the record would show that their retirement age was 65 (the male retirement age at the time), rather than 60.
Surely more likely they simply wanted to retire at 60? Although complaining about being outed would obviously garner more sympathy.
Relevant paragrapsh from the judgment
Goodwin vs UK
16. In 1996, the applicant started work with a new employer and was required to provide her National Insurance (“NI”) number. She was concerned that the new employer would be in a position to trace her details as once in the possession of the number it would have been possible to find out about her previous employers and obtain information from them. Although she requested the allocation of a new NI number from the Department of Social Security (“DSS”), this was rejected and she eventually gave the new employer her NI number. The applicant claims that the new employer has now traced back her identity as she began experiencing problems at work. Colleagues stopped speaking to her and she was told that everyone was talking about her behind her back.
17. The DSS Contributions Agency informed the applicant that she would be ineligible for a State pension at the age of 60, the age of entitlement for women in the United Kingdom. In April 1997, the DSS informed the applicant that her pension contributions would have to be continued until the date at which she reached the age of 65, being the age of entitlement for men, namely April 2002. On 23 April 1997, she therefore entered into an undertaking with the DSS to pay direct the NI contributions which would otherwise be deducted by her employer as for all male employees.
So they did make a claim of entitlement to a pension at 60, which is obviously no longer an issue in the UK.
Para 16 seems to be why there is a clause in the GRA which prevents anyone from disclosing that a person holds a GRC if they have obtained this knowledge in a professional capacity. But if the employer can't disclose this information, and it seems reasonable that in many cases an employer might need to know the sex of their employees, there is no need for a change of NI number.