I'm not a native speaker, but I'm pretty sure that a 的 can be removed if it would've been repeated multiple times. For example, "this is my favorite movie" would technically be 这是我的最喜欢的电影, but something like that would usually be written as just 这是我最喜欢的电影. In this case, the 的 can sort of apply to both the 我 and the 最喜欢, if that makes sense.