Section 10 of the German Patent Act defines the constituent elements of contributory infringement as follows: a patent has apart from prohibiting direct infringement the further effect that a person not having the consent of the patentee shall be prohibited from supplying or offering to supply within the territory to which the Act applies a person, other than a person entitled to exploit the patented invention, with means relating to an essential element of such invention for exploiting the invention, where such person knows or it is obvious from the circumstances, that such means are suitable and intended for exploiting the invention. This does not apply when the means are staple commercial products, except where such person induces the person supplied to commit acts of direct infringement.