I would expect that the Chemlak is correct.
The determinant is *probably* "does it contain Golarion-specific" content (and thus, protected Intellectual Property {"Closed Content" in OGL terms})? If yes, it needs the corresponding PDF from Paizo; if no, it is open content and would not (as, technically, anyone could create and sell a Realm with the same Open Content)
The determinant is *probably* "does it contain Golarion-specific" content (and thus, protected Intellectual Property {"Closed Content" in OGL terms})? If yes, it needs the corresponding PDF from Paizo; if no, it is open content and would not (as, technically, anyone could create and sell a Realm with the same Open Content)