Braindrain
·Yep, done as a tax dodge. I'll try to dig up the history of it I have somewhere, but I recall when this was done pre war it was legal to set it up this way, but no longer as the loophole is closed. They are grandfathered.
During or just after WW2, I believe. UK was introducing all sorts of taxes so Rolex decided to pack up and HQ in Geneva.