Patent offices offering third-party observations/submissions generally impose a limit on the number of TPOs than can be filed anonymously. Do PCT TPOs count against this limit?
This article seems to loosely imply it does count:
Moreover, it is only possible to comment on novelty and inventive step [in a PCT TPO]. Third parties may therefore prefer to wait until national/regional phase proceedings before submitting more detailed observations.
Though this article seems to imply the opposite:
Thus, the main objective of improving the quality of patents or of preventing frivolous and unworthy patents from being granted gets defeated if the national patent offices choose to ignore the comments. In such cases, the third party who filed the observation [at the PCT] has to ultimately wait for the national phase prosecution in order to take appropriate further action to challenge the invention and present its arguments.