This part doesn't make sense to me:

> Read fairly, references to sex in this provision can only mean biological sex. People are not sexually oriented towards those in possession of a certificate.

Is this implying that sexual orientation is instead based on biological sex? Because it definitely isn't. You don't need to see someone's genitals to know if you're attracted to them, and you most definitely don't need to see their chromosomes. You can say you wouldn't consider having a relationship with a trans person if you like, but (apart from asexuals) you definitely can't say you aren't attracted to at least some of them, since (despite what some ideologues insist) you can't reliably tell whether someone is trans or not at a glance.

This is really positive news for women in the UK. Up until now there's been considerable uncertainty over exactly who, by law, can have access to nominally single-sex spaces. The Supreme Court ruling clarifies this, and probably the most immediate impact of this will be on tribunal cases currently in progress.

There are two that have been widely publicized, involving female nurses working for NHS hospitals who've objected to male colleagues being allowed by hospital management to use female changing rooms on the basis of these males calling themselves women. This ruling means that the tribunals can now be expected to judge this policy, and the punitive actions of the NHS against female employees who objected, to be incompatible with the law.

At the same time the ruling clarifies that the law still protects people who have gender identity self-beliefs from harassment and discrimination, which is also good news and a sensible middle ground for how society should regard this phenomenon.