Gina Miller, investment manager and philanthropist has become a thorn in the side of Theresa May since launching Bexit the legal case. The case, that forces May to take any decision on Article 50 to parliament before it is triggered, has been ruled as valid by three high court judges.  The government has already announced plans to fight the verdict in the Supreme Court, which will rule in January, but have acknowledged an eventual defeat will be a serious setback to leaving the European Union.

Miller is the co-founder of Miller Philanthropy, which she launched with her husband Alan. The couple also launched the True and Fair Campaign, aimed at cutting charges on ISAs and rooting out “dishonesty” in the financial services industry.

Miller argued that the prime minister should not be able to use royal prerogative to invoke Article 50 — the official process of leaving the European Union. Instead, the PM, should be legally required to secure parliamentary approval before triggering Britain’s departure from the 28-nation bloc.

When asked in an interview with Business Insider back in August, if she was a ‘remainer’ Miller said “Actually, I managed to fall out with both sides — Leave and Remain. I thought the question was far too binary and I kept saying I was not a remainer — I was for remain, reform, and review. As people in business know, if you just sit on your hands and don’t progress with the changing environment, you won’t reform and improve the existing relationships you have. Whilst I agree that we should remain, I don’t believe that it’s something to be taken for granted.

The judgement may end up having far greater repercussions than Miller anticipated. The challenge could force the Prime Minister to call a snap general election next year to ensure she has enough support to get her Brexit plan through the House of Commons.

The ruling had an immediate impact on the markets with the Pound rising to a three-week high against the US dollar.  GBP surged to 1.248 against USD from a low of 1.21.  This is still a long way short of the 1.483 back in April 2016.  Technical analysis suggests that the current move  should still only be viewed as corrective, and not the beginning of a recovery.