Applied and was invited for a first HR interview where the role was explained and I introduced myself. Was then invited for a more technical interview where I was asked e.g. to describe a complex financial product

It is simply a waste of time applying for this company, trust me. I went through 4 steps before being rejected. None of the steps was even closely related to trading. The steps were: i) online test; ii) competency-based interview; iii) home task; iv) case-study interview. The hometask was tough (two exercises, one in Python and one in SQL to do in 1 week). The case study was similar to those conducted at McKinsey, very easy (How do you optimise a process? How do you increase revenues?). I nailed every single step of the interview process. Yet, I received a rejection. The guy who interviewed me in the fourth step was not even listening to the answers I was giving: he kept chatting / writing emails while I was speaking. He was from a completely different department, so obviously he did not care about spending efforts to recruit the right candidate because that candidate would not work with him anyway!! I honestly gave very good answers in the fourth step, so I really do not understand why I was rejected. I do not think many candidates have a STEM PhD from Cambridge. The worst thing is that it took them more than a month to get back to me after the home task. They had completely missed my application. I had to message the guy who interviewed me in the second step in order to chase up with the HR. Only thanks to him I was progressed to the fourth step a few hours later. The HR had completely ignored the email I sent her 2 weeks before. In conclusion, I think this company still needs to grow significantly before being able to be called "company". At the moment they are just a large startup with a recruitment process that simply does not work. So please, don't waste your time with your application, because it takes a lot of time to go through all of this and in the end it is not worth.