2. Amendments made by applicants of their own volition
For Euro-PCT applications where the EPO acted as ISA or SISA, any amendments filed in response to the communication under Rule 161(1) (see E‑IX, 3.3.4) are made by the applicant of their own volition. This means they may be submitted to overcome objections raised in the WO‑ISA, IPER or supplementary international search report or they may be suggested for some other reason, e.g. to remedy some lack of clarity that the applicant has noted in the original documents. In order to avoid delays, care should be taken to comply with the requirements of Rule 137(4) when filing such amendments. Furthermore, the applicant may also file observations in place of or in addition to amendments.