A Prenuptial Agreement was overturned by The Court of Appeal recently in December 2018 even though the parties had signed three Prenuptials in three countries to try to cover the position in all respects.
This case seems rather complicated however and the reasons are bound to become clearer in due course. There had been a relationship of 15 years and with two children.
Effectively all of these Agreements seem to have come unstuck on the quite logical ground that children had been born and that the Agreement was far too one-sided and wasn’t fundamentally reasonable. This decision does seem rather sensible and it would seem difficult for such a decision to be overturned at the Supreme Court (Former House of Lords).