Clarifying the difference between patent entitlement and the "first-to-file" doctrine, the House of Lords recently ruled in a preliminary action in the United Kingdom that Yeda Research and Development Company Limited was entitled to continue with its action to establish their entitlement of the patent covering the anti-cancer drug Erbitux. Yeda Research and Development Company Limited v. Rhone-Poulenc Rorer International Holdings Inc & Others [2007] UKHL 43.

Unlike the United States, the United Kingdom’s patent system is based on a "first-to-file" system, which means that the first inventor to file a patent application will be awarded a patent, as opposed to the inventor who first invented it (in reality these are almost always the same person). However, this does not mean that a patent will be granted to anyone who has made a filing; the person must be entitled to file the application by virtue of being the inventor or a successor in title of the inventor. It is therefore possible for patent entitlement disputes to arise under a first-to-file system when different parties are both claiming to be the inventor of the same invention. A number of these disputes have come to trial in the UK courts in the last few years, almost always in relation to an invention arising out of a collaboration between the parties or in circumstances where employees involved in the invention have moved between the parties.

The 2005 case of Markem v. Zipher fell into this latter category. Zipher was a company founded by several individuals who had previously been employed by Markem. Zipher went on to file a patent application that Markem contended should have belonged to Markem as the information underpinning it was allegedly developed whilst the founders of Zipher were employed by Markem. Ultimately, the Court of Appeal dismissed this, finding that the invention was made after the employees had left Markem and therefore rightly belonged to Zipher and that any information used in the making of the invention, even if originating at Markem, was not confidential. In reaching this conclusion the Court of Appeal found that a person (A) who claims to be entitled to a patent which has been granted to someone else (B) could not succeed merely by showing that A had been the inventor and that B had not. In particular, "A must be able to show that in some way B was not entitled to apply for the patent, either at all or alone. It follows that A must invoke some other rule of law to establish his entitlement—that which gives him title, wholly or in part, to B’s application."

Here, the House of Lords came to consider this ruling of the Court of Appeal, and in doing so, overturned it. The House of Lords found that the UK Patents Act provided an exhaustive code for determining who is entitled to the grant of a patent, the person entitled being the inventor or their successor in title, the inventor being the actual devisor of the invention. If such a person is that devisor then they will prima facie be entitled to the patent, and no other rule of law need be invoked to establish this. In reaching this conclusion, the House of Lords made clear that "first-to-file" is a rule about validity and should not be confused with issues of entitlement. The doctrine of "first to file" merely settles the question as to which patent will be valid when two inventors have independently devised and applied for patents for the same invention. Instead, issues of entitlement arise where multiple parties, all of whom will have had some link or relationship, are disputing who is ultimately responsible for a single instance of devising an invention.

Practice Note: Ultimately this case highlights that in determining entitlement to a patent it is important to establish the facts surrounding the creation of an invention, even in a first-to-file system. In proving entitlement, accurate records about who did what and when are invaluable. This needs to borne in mind particularly when an invention is devised as part of a collaborative effort or in any other circumstance in which divergent interests arise.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.