The current system made patent registration up to 60 times more expensive in Europe than in China and will now be binned in favour of a one-size-fits-all pan-European process.
But Spain and Italy refused to join the scheme because of language concerns.
Speaking on the eve of the formal adoption, Michel Barnier, the EU's Internal Market Commissioner, said: “Costs will be reduced by over 80%. In the history of European integration there have not been many steps forward of such significance, in such an important area. This will be a major boost to competitiveness.”
Signing off on a plan first considered in 1973, 24 of the EU's 27 industry ministers meeting at the Competitiveness Council in Brussels put their names on the agreement to allow inventors to register their idea with one EU agency.
Under the previous system, patents had to be registered separately in individual EU countries.
Italy signed the agreement, even though it has said it will not use the unitary patent. It and Spain – which did not sign – believe the new patent system does not give due recognition to their languages.
Bulgaria refrained from signing until certain domestic administrative matters are resolved. Poland also decided not to sign the agreement due to the potential negative impact of the unitary patent to its economy – though it has not ruled out joining up in the future.
The European Parliament approved the patent last December in Strasbourg, so the agreement will enter into force once 13 countries have ratified it.
Patents grant the exclusive legal right to develop and exploit an idea for a limited period of time, ensuring innovators benefit from their inventions.
Apart from wrangles over language another block to the creation of the unitary patent involved a bitter dispute between Germany, France and Britain over which country should host the court that will adjudicate in patent disputes.
Court divided into three to resolve dispute
At a summit in June 2012, German Chancellor Angela Merkel, French President François Hollande and British Prime Minister David Cameron agreed to split the court between three centres – Munich, Paris and London – depending on the type of patent.
Under the compromise, the court's headquarters will be in Paris, with some functions in London and Munich. Infringements of patents in life sciences will be heard in London, whilst engineering and physics-related cases will be dealt with in Munich.
Questions remain over practical aspects of the new system, however, such as whether it can really be up and running by the beginning of 2014, and how division of labour at the three courts will be managed.