Editing Doctrine of equivalents (section)

=== Ireland ===
Ireland appears to subscribe to a doctrine of equivalents. In ''[[Farbwerke Hoechst v Intercontinental Pharmaceuticals (Eire) Ltd]]'' (1968), a case involving a patent of a chemical process, the High Court found that the defendant had infringed the plaintiff's patent despite the fact that the defendant had substituted the starting material specified in the patent claim for another material. Expert evidence showed that any technician who failed to obtain a good result using the specified starting material would try the replacement material. The two materials were therefore held to be chemically equivalent, and the replacement of one with the other by the defendant did not prevent a finding and injunction against him.