It is generally thought at the EPO that it is a Bad Thing to have two patents granted to the same applicant to cover the same invention. This is known as Double Patenting, and there are provisions under national law to prevent this from happening (section 18(5) of the UK Patents Act 1977, for example). Unfortunately for the EPO (and as confirmed by T 587/98), there is no such provision in the EPC. Or so the IPKat thought.
"Article 60 EPC (identically worded under the EPC 1973 and 2000) states 'The right to a European patent shall belong to the inventor or his successor in title' [...] From this the Board deduces that under the EPC the prohibition of double patenting applies and that the inventor (or his successor in title) has the right to the grant of one and only one patent from the European Patent Office for a particular invention as defined in a particular claim. Once a patent has been granted to the inventor (or his successor in title) this right to a patent has been exhausted, and the European Patent Office is entitled to refuse to grant a further patent to the inventor (or his sucessor in title) for the subject-matter for which he has already been granted a patent" (point 2.1 of the reasons)The IPKat will leave others to determine whether this reasoning is sound or not, but in the meantime he would like to suggest that it might be time to ask the Enlarged Board a couple of questions, since we now have two decisions that clearly arrive at different answers to the same question. These questions could, for example, be:
1. If two or more applications for a patent for the same invention having the same priority date are filed by the same applicant or his successor in title, does the EPC have a provision to, on that ground, refuse to grant a patent in pursuance of more than one of the applications?2. If so, what is this provision and how should it be applied?