Article 64

(1) A European patent shall, subject to the provisions of paragraph 2, confer on its proprietor from the date  on which the mention of its grant is published in the European Patent Bulletin, in each Contracting State in respect of which it is granted, the same rights as would be conferred by a national patent granted in that State.

(2) If the subject-matter of the European patent is a process, the protection conferred by the patent shall extend to the products directly obtained by such process.

(3) Any infringement of a European patent shall be dealt with by national law.

UPC Case Law

IPPT20260116, UPC CFI LD Paris, IMC Creations v Mul-T-Lock 
Unitary patent valid (Article 65 UPCA) and infringed (Article 25 UPCA).  A unitary patent takes effect retroactively, (Articles 64(1) , 68 EPC , Article 4(1) Unitary patent regulation) as of the date of the European patent became a unitary patent, pursuant to the combined provisions of Articles 64(1) and 68 of the EPC and Article 4(1) of the Unitary patent regulation.  Furthermore, the patent as granted, so long as it has not been judicially invalidated, is deemed valid from the date of its grant.