I was confused by GP until I reread it and realised that the operative word is how. I don't know anything about Swiss law or Google internal policy but I think

I was confused by GP until I reread it and realised that the operative word is how. I don't know anything about Swiss law or Google internal policy but I think what he's saying is that it's illegal in Switzerland to dictate how your employees socialise with each other outside of work (and perhaps to dictate anything else about how employees behave in their private lives?), not that it's illegal for employees to socialise at all.