The UK made good on its announcement and officially withdrew from the Agreement on a Unified Patent Court and thus from the plans for an EU patent. This was announced by the Government in London to the General Secretariat of the Council of the European Union.
The intention of the UK’s withdrawal from the European Union was to no longer be bound by Union law and by the CJEU. This objective was not compatible with participating in the joint “EU patent” project. Find a summary of the problems associated with the UK’s withdrawal here: Effects of Brexit.