The trick in this is twofold 1: define "competitors", either by name or business sector.2: Keep looking for other jobs, since without an alternative your negotating posture is weak.Be clear that this is a negotiation and if I were your HH I'd be doing that, I trust yours is ?MiloRambaldi, I am not a lawyer but as you can imagine employment contracts are part of my work.A properly written contract specificies the legal system in which it applies, but by defaul the court will decide what the two parties "meant" when they wrote it.So if you are a German, worknig in a German bank in Germany, that's fine. (this rule does not apply in Sweden wheree the daffy court system just make shit up)The jurisdiction does not have to be the one where the work happens, for instance Russian courts are so corrupt that people walk away from deal rather than have them as jurisdiction.So London handles a lot of contracts where nothing happens in England at all, including a large % of Sharia finance.One trick used by US firms operating outside the US is to make te jurisdiction a mildly corrupt and seriously expensive jurisdiction like NY, even if you'll be working outside the US. This makes defending any case very expensive.Every jurisdiction has different interpretations and restrictions on what is enforceable. For instance EU countries have riles that say if a firm transfers a business to another company, employment is sticky to the business not the company.The "reasonable" rules on how long you can be prevented from working are long and have geographical and as well as business boundaries. The geography thing comes from a time when NY, London, et al were different worlds, now of course most work that a quant may do can be done anywhere, even Frankfurt.