If a category is applicable to a profile, normally the parent category would also be applicable, but should not be provided as it is already provided implicit.
Special thing with stickers and One Name Studies: The ONS sticker provides the profile automatically with the global category of that name (i. e. Ostermann Name Study). Additional there is the state-based category (i. e. Nordrhein-Westfalen, Ostermann Name Study). It's OK.
But now, I removed the sticker, because I don't like the stickers on the profiles. Should I provide the category (i. e. Ostermann Name Study) directly? It would be redundant. But is this neccessary for apps to evaluate? For statistics?