The EPO Boards of Appeal convened recently to offer a final ruling in respect of EP2771468, a patent granted to the Broad Institute in respect of CRISPR/Cas9 gene editing technology. This case has attracted a lot of attention, not least because of the potential commercial value of the patents at hand, as well as the background of long-standing disputes between the various parties holding CRISPR patents across the world.
What is CRISPR?
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) technology is a novel DNA editing tool which is faster, more cost-efficient, and more accurate than previous gene editing techniques. Indeed, there was some speculation that the most recent Nobel Prize for physiology or medicine might be awarded to the minds behind CRIPSR, before this was awarded to Kaelin Jr, Ratcliffe, and Semenza for their discoveries of how cells sense and adapt to oxygen availability.
Ultimately, the technology can be used to permit scientists to rapidly make cell and animal models for the purposes of medical research, as well as providing many options for medical diagnostics, and the techniques are widely used around the world.
EP2771468 was filed on 12 December 2013, as an International (PCT) application, claiming a long list of priorities to earlier US applications. The publication of grant occurred on 11 February 2015. Several oppositions were launched, starting in October 2015, which asserted that the patent was invalid.
The claims themselves were directed towards a composition comprising a CRISPR-Cas system chimeric RNA or a CRISPR enzyme sequence, which are modified to improve their stability.
The patent itself is a fairly meaty read, with the International application as published running to 162 pages. The field of technology here is one with dense impenetrable jargon (much like patent law itself!), but this is beside the point. The merits of the appeal hinged on a simple question – was the application entitled to priority?
The law of priority for patents stems originally from the Paris Convention, which recites in Article 4(A)(1):
Any person who has duly filed an application for a patent […] in one of the countries of the Union, or his successor in title, shall enjoy, for the purpose of filing in the other countries, a right of priority during the periods hereinafter fixed.
Why is this important? Well, the Broad Institute filed their original US patent application having four inventors, also named as applicants. When filing in Europe (via the PCT filing), however, one of the inventors was omitted, Professor Luciano Marraffini of Rockefeller University, New York.
If Professor Marraffini had not, as asserted by the opponents, assigned his right to the invention correctly to the Broad Institute by the time the European application was filed, then the Broad Institute were not entitled to claim the priority right. This meant that the effective date for the assessment of prior art changed. Here, this meant that different citations, much more destructive to patentability, became citeable, which in turn would lead to revocation of the patent.
EPO case law is quite clear in this regard. T788/05 clarified that a sole applicant who was one of several joint applicants on a first filing cannot give rise to a separate priority right. The right of priority is jointly owned but indivisible. The applicant of the European patent application must be the owner or successor in title to all of the rights of the individual applicants of the priority application as of the date of filing of the European application, or in this instance, PCT application, for a valid priority claim to be made.
If the EPO case law is so clear, then how did this case reach an oral hearing? Crucially, the USPTO have a different interpretation of how a valid priority right can form – the later application needs only a single inventor in common in order for a valid priority claim to be made.
Essentially (and in much simplified terms), the Broad Institute argued that, given that the priority applications were US filings, then US law should govern how priority can be claimed. Additionally, much semantic argument was heard about the meaning of the term any person as outlined in the Paris Convention.
This line of argument threatened to lead the Boards of Appeal to refer the matter to the Enlarged Board of Appeal, which would have significantly extended the uncertainty regarding the status of the patent, but eventually finalised their decision to revoke the patent, finding the priority claim invalid.
Overall, the decision of the Board of Appeal is much as had been expected to European observers. The prevaricating over this matter has ended, and the final written decision of the Board is expected soon.
What can we infer from a practice perspective from this resolution, however? Primarily, whilst the direction in the UK, at least, is towards excusing sloppy claim drafting, the law of priority remains strict, to the point of being lethal to viably patentable technology. In this instance, the Broad Institute potentially have nine patents which have questionable priority claims.
Given the divergence of US and European law in this regard, patent practitioners need to be very aware of potential issues in respect of entitlement and ownership, and how this can have a knock-on effect on the validity of patents.