According to a report from a German newspaper (the Frankfurter Allgemeine Zeitung), the German Federal Constitutional Court (the Bundesverfassungsgericht) asked the Federal President to suspend the signature of the legislation implementing the Unitary Patent Package voted on 31st March by the German Parliament necessary -together with the German executive’s and its publication in the German Federal Law Gazette- for it to become legislation.
The German Constitutional Court in fact received a complaint in April 2017 (2 BvR 739/17), from a currently unknown source, challenging the constitutionality of the legislation enabling the ratification of the UPC agreement. Although the grounds remain unknown to the public, the Court considered this complaint justified enough to request the Federal President not to sign the bill and examine the complaint before ratification.
The Constitutional Court spokesperson confirmed that the President had indeed agreed, as a preliminary measure, to delay signing the bill.
It is however difficult to say whether this unexpected event will slow down, again, the ratification process of the UPC agreement. In fact, Germany still has time to deposit its instruments of ratification by September 2017, thus allowing the UPC to be launched by the beginning of 2018.