At the EPO, the number range starting at 000001 (PCT/EPyyyy/000001) is used for paper filings (including faxes). The number range starting at 025000 (PCT/EPyyyy/025000) is used for filings made via Web-Form Filing. The number range starting at 050000 (PCT/EPyyyy/050000) is assigned to electronic filings made using CMS, OLF or ePCT.[]
Source: http://www.epo.org/law-practice/legal-texts/html/guidelinespct/e/a_ii_1_5.htm
Date retrieved: 17 May 2021