European Patent Attorneys

The European Patent Convention (EPC), the multilateral treaty providing the legal system according to which European patents are granted, contains provisions regarding whether a natural or juristic person (i.e., a party to the proceedings) needs to be represented in proceedings before the European Patent Office (EPO).

There is no general obligation to be represented by a professional representative to act in proceedings before the EPO. However, a person not having either their residence or place of business within the territory of one of the EPC Contracting States (a "non-European party") "must be represented by a professional representative and act through him in all proceedings", except for filing a European patent application. Proceedings include grant proceedings (as applicant), opposition proceedings (as patentee, opponent or intervener pursuant to Article 105 EPC), limitation and revocation proceedings (as patentee), and appeal proceedings (as appellant or respondent).

Representation of persons who must be represented and persons who need not be represented but want to be represented must be by a professional representative, or, if the party is a "European party", the representation may be by an authorised employee or by a legal practitioner. A legal practitioner representing a party before the EPO must be qualified in an EPC Contracting State, must have his place of business in that State, and must be entitled in that State to act as a professional representative in patent matters. Both authorised employees and legal practitioners "must file a signed authorisation or a reference to a general authorisation already on file". Subject to these rules, a party has the right to be represented in the manner he chose.

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Wikipedia