4.1.17.Is it possible to correct defects in the demand? 

4.1.065If the demand does not comply with the requirements, the EPO as IPEA invites the applicant to correct the defects within one month of the date of the invitation. If the applicant complies with the time limit, the demand is deemed to have been received on the actual filing date, provided that the demand as submitted sufficiently identified the international application. If the applicant does not comply with the invitation in due time, the demand is deemed not to have been submitted. 

4.1.066Where there is more than one applicant, a frequent defect concerns failure to provide the required indications and/or the signatures of all the applicants. However, if the required indications are available in respect of one of the applicants entitled to file a demand and the demand is signed by one of them, this is considered sufficient and no invitation will be issued (see point 4.1.053).