Patents and the Public Interest – When Should a Final Injunction be Refused?

By Brian Whitehead, Partner

When should a court, having found a patent to be valid and infringed, refuse to grant a final injunction, on grounds that it would not be in the public interest? This issue arose in the case of Evalve & Abbott v Edwards Lifesciences. Birss J held that Evalve’s patents, relating to a medical device for treating a cardiac condition, mitral valve regurgitation, were infringed by Edwards Lifesciences’ PASCAL product ( In a second judgment handed down on the same day (, he considered whether an injunction should be granted, and if so on what terms.

The starting point is that the normal remedy for infringement of a patent is a final injunction. However, patents in certain fields – particularly the medical field – raise wider issues of public interest. If the granting of a final injunction would result in the withdrawal of a life-saving drug or device, without an adequate alternative, the judge can refuse to grant such an injunction, or at least limit its scope.

Birss J reviewed the case law, and summarised it as follows:

  • Patent legislation itself already places limits on patent rights in order to safeguard the public interest. That includes a power to make life saving treatments available to the public without the permission of the patentee;
  • The power to refuse a final injunction should be used sparingly and in limited circumstances;
  • Care must be taken in awarding damages in lieu of an injunction. If the damages are to compensate the patentee for lost sales, the likelihood is that the infringer’s profits will be wiped out, leaving it with no incentive to sell in the UK. That would have the same practical effect as an injunction;
  • If on the other hand damages are awarded on a (lower) reasonable royalty basis, that would amount to a compulsory licence (when none would normally be available), meaning that the patentee would be ordered to bear financial losses in the public interest.

The judge adopted a very restrictive approach as to whether there is a genuine public interest in PASCAL’s continuing availability. It was not enough, as Edwards had done, for a defendant to put forward evidence from clinicians that they preferred to use PASCAL over the patentee’s product. A defendant must go further and produce “reliable clinical data which identifies any class of patients for which it is more likely than not that PASCAL is the only viable treatment [or] reliable clinical data which identifies particular classes of patients or anatomies for which it is more likely than not that PASCAL would be a better treatment than the currently available MitraClip”.

Taking all the above into account, the judge was not persuaded that there was a wider public interest in allowing sales of PASCAL to continue. The parties had agreed that there should be a carve-out allowing its use in patients when a device made to the patents has already been unsuccessful. Other than that, therefore, a final injunction was granted.

This area of law is relevant primarily to medical patents, although it is conceivable that patents in other fields could raise issues of public interest. This is a developing area of law, and Birss J’s judgment is unlikely to be the last word. As a detailed and comprehensive overview of the relevant law and principles, however, this judgment is certainly a useful contribution to the ongoing debate.