Appearance dictated by technical function

The exclusion of appearance dictated by technical function prevents the appearance of a product whose features are solely dictated by its technical function from being protected as a design. It is laid down in Article L. 511-8 of the French Intellectual Property Code and Article 8 of Regulation (EC) No 6/2002, which also exclude interconnection features. It marks the boundary between design law, which protects aesthetics, and patent law, which protects technology.

The test of exclusive functionality

The Court of Justice of the European Union holds that a feature of appearance is solely dictated by technical function where that function is the only factor which determined it, visual considerations having played no part in its design. The existence of alternative shapes capable of achieving the same technical result is not decisive: the multiplicity of forms theory, long applied by part of the French case law, no longer suffices to rule out the exclusion. The assessment is objective and takes account of all the circumstances, in particular patents filed on the product, the holder’s other designs and its marketing communications. Where only certain features are functional, they are disregarded in the comparison and the right survives if the others suffice to give it individual character (caractère propre).

Interconnections and modular systems

A second exclusion covers the appearance of a product whose shape and dimensions must necessarily be reproduced so that it can be mechanically connected to, or placed in, around or against another product, so that either product may perform its function. These so-called ‘must fit’ features remain free, in order to preserve compatibility and competition in complementary products. By way of exception, designs allowing the multiple assembly of interchangeable products within a modular system remain protectable, a provision made for construction toys and modular furniture.

Interplay with trade marks and patents

The same concern drives trade mark law, where a shape necessary to obtain a technical result is refused registration, but the tests do not coincide: in trade mark law, the presence of minor non-functional elements does not save the sign, whereas in design law functional features are merely disregarded in the comparison. A technical shape belongs to the patent system, for a limited term, if it is new and inventive. The exclusion is raised in defence in most infringement actions concerning technical products, by way of an application for a declaration of invalidity.

Key points

A feature of appearance is excluded from protection where technical function is the only factor that determined it, whether or not alternative shapes exist. Interconnection features are also free, except within modular systems. From the design stage onwards, aesthetic choices should be documented and the appearance should not be presented as purely functional in patents or advertising, and, in defence, those same documents should be used to challenge the right.

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This glossary entry is general in scope and does not constitute legal advice.

Dhenne Avocats is a patent litigation firm. Matters outside that field, such as trade marks, designs, copyright and IT contracts, are handled by practitioners the firm works with regularly, and by the firm itself when they arise in a patent dispute.

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