From my basement in London: Probably specific countries.

I think there are at least two separate issues here; some countries have health and safety laws requiring natural light, while others require natural light in newly-built offices (as a condition of planning etc). Can you build an office in London these days that doesn't have natural light in the main spaces? I'd be sceptical.

Old building. Managed offices, completely gutted internally last year. I don't know if that wound count as new build. Probably not.

No, definitely not. You get away with all sorts of things with a sufficiently old building.

Is it an old building? There are some basement offices in London, and presumably other countries, with either no windows or pointlessly small/ineffective ones (like those little glass blocks you see on the pavement occasionally). I wonder if light regulations would have to have exclusions for old buildings that are impractical to change (a bit like minimum platform widths at train stations don't apply to some old stations).

There are planning regulations in the UK preventing new developments from "stealing" light from existing buildings, there's also a Right to Light.

Eg http://www.right-of-light.co.uk/services/calculations-and-re...

>There are planning regulations in the UK preventing new developments from "stealing" light from existing buildings,

Sounds like backdoor NIMBYism