Since I don't think this has been answered so far: All complaints about umpires should go to the referee. In this case, that is Carsten Koch ( carsten.koch<insert '@'>gmx.net ). However, a generic "I don't like this umpire" complaint is extremely unlikely to be helpful, and thus will have little effect except you appearing to be a lunatic. Therefore, your complaint should go into more detail of what do you think is the precise problem with the umpiring to avoid So can you elaborate what your problem is? I assume you are arguing for one or more of the following: 1. The umpire / service judge should not have called faults because there weren't any under current rules. Technical officials are sometimes wrong, and precise video material (like Hawk Eye) can show that. The public videos don't show LD's feet, so aren't of any help here. If you have high-quality video material, please do publish it so we can all review it and incorporate it into future umpire training courses and discussions. 2. The umpire / service judge should not have called faults despite them being warranted. Umpires can sometimes be lenient towards faults. In fact, if an umpire is not sure a fault has been committed, they are encouraged to let it slide. Needless to say this is a really weak argument. 3. You are discontent with the way the umpire handled the fault calls. That's probably the strongest argument - I personally think the umpire's (and to a lesser degree the service judge's) hand signals are not as clear as they could be, and turning off the microphone may be questionable. 4. You want to change the rules (or regulations). If that's the case, do not contact the referee. Instead, contact the BWF Technical Officials Commission. If you really want to effect change, you should found a movement to change rule §9.1.2 and convince a significant number of high- and low-level players, coaches and officials before addressing the commission. 5. You want a better visual presentation. If that's the case, contact the video team / tournament organizers. There's a strong point to be made that the camera could show the hand signals and a view to judge the faults ourselves, if necessary in instant review. Of course there is a financial trade-off - sure, with a hundred instead of a dozen cameras we'd have way better pictures, but it would be prohibitively expensive. 6. If you want better commentary, contact the commentators. That's one thing I'm thinking about preparing and eventually doing myself , with a list of esoteric things to know about umpiring. In particular, Gillian Clark and Ian Wright may want to review rule §16.7 and RTTO §22.214.171.124.