In the past I have seen this happen on a number of occasions – particularly back in the days of mortgage endowment complaints. It sounds like there are a number of possible issues in the background here (old mortgage case, PI firm dealing with it etc.) and, as with any complaint, what may or may not be appropriate will depend on the circumstances of the individual complaint / case. In general terms, though, if someone believes that they have reason to commence a court action then they are entitled to do so. The law does not insist, as far as I am aware, that any available complaints process must be fully explored and exhausted prior to taking a case to court. The ability to dismiss a complaint (or the ability of FOS not to consider it) that is set out in DISP 2.8 is founded in Statute (Limitations) that would also apply to a Court action. If the complainant or someone acting on their behalf wants to take a case to court, they can do; it is possible that the complainant’s representatives know that FOS will not take the case on so they have simply circumvented that. They should realise, though, that the defendant (the adviser or their PI firm on their behalf) may well also seek to have the action time-barred. Hope this helps.