Saint-Gobain v. Knauf Insulation, Belgian Supreme Court, 12 March 2015
Patent - Scope of protection - Theory of equivalents - Amendment of the patent application - Interpretation of the granted claim - Impact of amendment on the scope of protection
A judgment deciding that the patent is not infringed, taking into account that the patent application as initially filed has been amended and that in its final version, the amended claim includes a feature which is missing in the challenged product, is consistent with Article 26 of the Belgian Patent Act (defining the scope of protection) and does not contradict the theory of equivalents.
In the present case, the judgment interpreting the amended claim of the patent as excluding from its scope products which do not exclusively contain glass fibers having a diameter of less than 8 microns, and deciding that the manufacturing of products containing glass fibers having a diameter greater than 8 microns in combination with glass fibers having a diameter less than this dimension is not a patent infringement, is legally justified.
The judgment of the Court of appeals was published on this blog here.
Read the decision (in French) here.
Head note: Fernand de Visscher and Philippe Campolini, Simont Braun