After a long period of discussion, finally on April 26, 2018, the UK government ratified the Agreement on a Unitary Patent Court (UPC).
Since Germany still has to ratify the Agreement, though, people are waiting for the ratification of the Agreement by the German government, which will finally enable establishment of the UPC. However, a pending constitutional complaint in Germany prevents the ratification from the government, and it is currently expected that the Federal Constitutional Court will make a decision in 2018. If the complaint is determined to be inadmissible, then the German government would probably ratify the Agreement in 2018. If not, then a substantive investigation has to be carried out by the Federal Constitutional Court, and a substantive decision may not be made until the first half of 2019, which would postpone the entry into force of the Agreement.