4.2.3.Is it possible to submit third-party observations? 

4.2.015Third parties may file observations on a PCT application during the international phase until 28 months from the priority date. Such observations are to be submitted using the online tool provided by WIPO and may be filed anonymously. If third-party observations are received, WIPO will inform the applicant and the applicant is permitted to reply. If the IPER has not yet been established at the time when observations or any reply are received, WIPO will forward the observations and the reply to the EPO acting as IPEA, which will take the observations into account when establishing the second written opinion, if it has not yet been established, and the IPER. Detailed information is contained in a guide entitled "ePCT Third Party Observations", published by WIPO.⁵⁹