I think the Court of Appeal is a little bit slippery in this one. It really skimps over the central argument that the National Football League makes: that an unincorporated association (e.g., the NFL) is deemed to be a "resident" of the state of its members not only for jurisdictional purposes, but also for purposes of other doctrines like forum non conveniens.
There's some doctrinal logic to this argument. But the Court of Appeal essentially neither accepts nor rejects it, simply saying that the two doctrines are somewhat different (true) and hence that while a "real" California resident is entitled to a strong presumption against a forum non conveniens stay/dismissal no such "strong" presumption attaches to a "partial" resident like the NFL.
As an outcome, that seems right. But the Court of Appeal essentially just articulates this rule ex cathedra rather than explaining why it's just. Which is too bad. Because I think there could be a pretty nuanced, and persuasive argument, on its behalf.
Then, when applying this rule to the case at hand, the Court of Appeal is slippery again, and only talks about the "strong presumption" (which it has previously rejected) -- as opposed to applying any presumption in favor of California on behalf of a "partial" resident like the NFL. This seems unfounded. I think it'd be more forthright to say that, yes, we'll go ahead and give the NFL some deference in favor of California, but here, even with such deference, New York is the right place for this litigation. Because, in my mind, that's totally true. But instead the Court of Appeal just articulates a mish-mash of thoughts that are only loosely (if at all) tied to the underlying (and evolving) standard. Whcih is too bad.
The net result is, again, one I think is correct. The NFL's insurance coverage action should take place in New York, not California. That's where the "NFL" does most of its "work". So when we decide whether or not the NFL's insurance policies cover the ever-increasing number of lawsuits from former players about concussions, it makes sense that the first-filed jurisdiction over New York resolve that issue. Notwithstanding the NFL's (understandable) contrary desire for a California forum.
Dealing with fictional entities is always a little difficult. Even when those fictional entities have a clear legal status; e.g., corporations. (See, e.g., Citizens United).
Dealing with entities that are not only fictional, but that may not actually even "exist" -- e.g., unincorporated associations -- is even harder.