I'd imagine Bilibili does pretty much manage the project. Isn't it at the very least a necessity that, if you're an outsider getting into the Chinese market, you need to make a subsidiary of sorts where a Chinese company has majority ownership? While Niji is usually there just for the tech in those scenarios, they do still hold at least some ownership, though. I can't find the source anymore, so assume I made this shit up, but I remember hearing that the sub-branches have different ratios of ownership, ex. VirtuaReal Star (IRL e-celebs with a model) being 100% Bilibili-owned.