>Also, if the US has a problem with a merger between two UK companies, do we in the UK have to abide by their ruling? If the UK business wants to do business i

>Also, if the US has a problem with a merger between two UK companies, do we in the UK have to abide by their ruling? If the UK business wants to do business in the US... yes. >What about if it is France rather than the US? Yes. >What if it's Russia? Yes. Companies must comply with local laws if they wish to conduct business in those countries. For example, countries may dictate requirements on the telecommunications products sold in their own countries. This is the one of the reasons my UK-sold iPhone has an FCC certification (and even Russian and Belarusian certifications) and iPhones in the US might have CE or UKCA certifications. This applies to less portable products, too: my Philips Hue bulbs have CE markings even though I'm not in the EU.