Registration is not a requirement for transfer of patent right in Germany

In some countries such as in Japan, the transfer of a patent right does not take effect until it has been registered in the register of a patent office.

In Germany, on the other hand, the transfer of the substantive right (Sachlegitimation) of the patent right takes effect upon the conclusion of the transfer contract (RGZ 151, 129, 135). The registration of a transfer of patent rights has only a declaratory effect in Germany (deklaratorische Wirkung) and is not a requirement for the transfer of patent rights to take effect (BPatGE 17, 14, 15f; BGH I ZB 5/67).

However, the registration of a transfer of a patent right have indeed some effect on procedural rights (Prozessführungsbefugnis) in Germany.

Section 30(3) of the German Patent Act, which governs the registration of transfers of patent rights, provides as follows:

Das Patentamt vermerkt im Register eine Änderung in der Person, im Namen oder im Wohnort des Anmelders oder Patentinhabers und seines Vertreters sowie Zustellungsbevollmächtigten, wenn sie ihm nachgewiesen wird. Solange die Änderung nicht eingetragen ist, bleibt der frühere Anmelder, Patentinhaber, Vertreter oder Zustellungsbevollmächtigte nach Maßgabe dieses Gesetzes berechtigt und verpflichtet.

English translation:

The German Patent and Trade Mark Office shall record in the Register a change in the person, name or place of residence of the applicant or proprietor of the patent and his representative and the person authorised to accept service if proof thereof is furnished to the German Patent and Trade Mark Office. Until the change has been entered, the former applicant, proprietor of the patent, representative or person authorised to accept service shall remain subject to the rights and obligations as provided under this Act.

Here,"the rights and obligations provided for in this Act" referred to in Section 30(3) of the German Patent Act refer to rights and obligations before the German Patent and Trademark Office (GPTO) and the courts (BGH I ZR 138/51). In other words, Section 30 (3) of the German Patent Act provides that the registration of a transfer of patent rights in Germany is a requirement for the transfer of procedural rights (Prozessführungsbefugnis) before the GPTO and the courts to take effect. 

For this reason, even after the conclusion of the transfer agreement, but before the registration of the transfer of the patent right, only the former patentee still registered in the Register of the GPTO may proceed before the GPTO and the courts, and the new patentee may not proceed, even though the new patentee fully possesses substantive rights. 

Thus, in Germany, after the conclusion of a transfer agreement and before the registration of the transfer, the substantive rights (Sachlegitimation) and the procedural rights (Prozessführungsbefugnis) do not belong to the same person (BGH X ZR 69/11).