Australian courts have recently taken a dim view of competitors claiming that the patentee has made unjustified threats of patent infringement. It is now clear that, in relation to the assessment of damages, it is necessary for the defendant to show any threats made by the patentee were directly the cause of loss or damage to the defendant.
In Mizzi Family Holdings Pty Ltd v Morellini (No 3)  FCA 870, damages relating to the unjustified threats were at issue. Mizzi held a patent for a sugar cane planting machine and sued Morellini for infringement. At first instance, it was found that Morellini’s machine did not infringe the patent and that Mizzi had made unjustified threats of patent infringement. (It was later found on appeal that Mizzi’s patent was invalid for false suggestion.) Mizzi had caused advertisements to be placed in trade journals, warning off potential customers of being in patent “infringement danger” if they were to buy competitive machinery to that disclosed in Mizzi’s patent application.
In light of a recent precedent, Morellini needed to establish causation between the threats and the damages claimed. The judge refused to find any liability even though customers did not want to take up the defendant’s machine, and “they were a bit cautious because they were waiting for all this to be over”. Although the judge accepted a general reluctance to deal with the invention, there was no finding that the reluctance was attributable to any threats.
The net effect of this decision is that it establishes the need for evidence of actual causation between the threat of patent infringement and the resulting loss by the
potential competitor. This is good news for patent holders but sets a high threshold for those wishing to invoke the unjustified threat ground in dealings with a patentee.