The start of the new system is currently expected for the end of 2021.
The Unitary Patent system is inextricably linked to the creation of the Unified Patent Court, which will have jurisdiction over Unitary Patents and "classic" European patents.
The EU regulations establishing the Unitary Patent system (No 1257/2012 and No 1260/2012) entered into force on 20 January 2013, but they will only apply as from the date of entry into force of the UPC Agreement, that is, on the first day of the fourth month following the deposit of the 13th instrument of ratification or accession (provided those of the three Member States in which the highest number of European patents had effect in the year preceding the signature of the Agreement, i.e. France, Germany and the United Kingdom, are included).
A Unitary Patent may be requested for any European patent granted on or after the date of entry into force of the UPC Agreement. For the state of play regarding ratification, please see the website of the Council of the EU.
Initially, Unitary Patents may not cover all participating Member States as some of them may not yet have ratified the UPC Agreement when it enters into force. Outstanding ratifications are likely to take place successively, so there may be different generations of Unitary Patents with different territorial coverage. The coverage of a given generation of Unitary Patents will stay the same for their entire lifetime, irrespective of any subsequent ratifications of the UPC Agreement after the date of registration of unitary effect. In other words, there will be no extension of the territorial coverage of Unitary Patents to other Member States which ratify the UPC Agreement after the registration of unitary effect by the EPO.