How Tufty’s Law detoxicates poisonous priority
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| It's not the coffee that kills; it's the poisonous priority ... |
Walter and Reinier write (nb for ease of reference, you can access the text of the European Patent Convention, or EPC, here):
Our posting “On poisonous priority: taking the debate further” raised the question whether it is fair and intended by the law makers that a priority application becomes a novelty-destroying prior right, if the subsequent application claims the invention in a different manner than in the priority application. This posting has attracted a record number of 87 replies, for which we are thankful. It would be a hard job to summarise and comment on all these comments. Luckily, this is not necessary, as a good solution to the problem at hand has emerged from this discussion. A solution with which we agree, which has been named “Tufty’s law”, and which is actually supported by at least one decision of a Board of Appeal (T 1222/11).
Tufty the cat has introduced this law on his own blog, while discussing poisonous divisionals. He himself and other authors (including Peter Arrowsmith) have correctly pointed out that this solves the problem of poisonous priorities too. Tufty’s law holds that a broad claim of the subsequent application can theoreticallybe divided into two parts, one of which is entitled to priority and the other which is inevitably novel over the priority disclosure.
Tufty
How would this work in practice? Let’s take the example given by Bart van Wezenbeek.
“Imagine that your invention has to do with a process using a metal, and you have the examples on iron (Fe) and gold (Au) in your priority application. Now some prior art has been found that discloses the same process with copper (Cu). Our 'smart' patent attorney limits his invention now to noble metals, thereby rescuing at least part of the invention. However, this would lack priority, which means that your own priority application with Au as example would destroy the novelty of your amended claim.”
If the examiner applies Tufty’s Law, then the subsequent application is not destroyed at all. The claim of the subsequent application can be theoretically divided into two parts: gold, and noble metals not being gold. The claim part to gold has priority from the previous application. Accordingly, the previous application is not novelty-destroying against this part. The other part of claim 1 does not enjoy the right of priority, but gold does not anticipate “noble metals not being gold”. Therefore, the claim to noble metals survives. Can we can hear Tufty purr?
“The use of a generic term or formula in a claim for which multiple priorities are claimed in accordance with Article 88(2), second sentence, EPC is perfectly acceptable under Articles 87(1) and 88(3) EPC, provided that it gives rise to the claiming of a limited number of clearly defined alternative subject-matters.”
The words “limited number of clearly defined alternative subject-matters” have been interpreted by several Boards of Appeal and judges in the sense that the claim of the subsequent application itself must define this limited number of clearly defined alternative subject-matters. However, G2/98 itself does not mention this. Moreover, this interpretation is in conflict with the very memorandum that is used as a basis, as well as the very wording of the first part of this sentence: “a generic term of formula”. Noble metal in the above example is a generic term. G2/98 does not state at all that one should literally claim “gold or a noble metal not being gold”, as some authors suggest. Quite the opposite: G2/98 clearly says that a generic term or formula is perfectly acceptable.
The Enlarged Board of Appeal has given no explicit interpretation for the words “limited number of clearly defined alternative subject-matters” , so we can only speculate as to what exactly was meant. However, the reasons and the memorandum do give guidance on what was not meant. In reason 6.4 of G2/98, the board concludes:
“Thus, the memorandum can be said to express the legislative intent underlying Article 88(2), second sentence, EPC.”
The Enlarged Board does not make any reservation with respect to the memorandum, so we may assume that the examples in this Memorandum are examples on how in the Board’s opinion one can claim a generic term or formula. There are three such examples, which have been mentioned in some of the comments to our initial post too: (a) broadening of a chemical formula (example with halogens), (b) broadening of range (temperature, pressure, concentration, etc.), and (c) broadening of field of use.“
The first example explicitly mentions the consequence of multiple priorities for one claim:
“A first priority document discloses a relatively narrow chemical formula supported by representative examples. A second priority document discloses a broader chemical formula which within its scope includes the narrower chemical formula, and which is supported by additional examples justifying the broader formula. If multiple priorities for one and the same claim are allowed, it will suffice to draw up a single claim directed to the broad formula. This claim will then enjoy priority from the first priority date to the extent that the compound in question comes within the scope of the narrow formula, and the second priority for the rest of its scope.”
Let’s take a closer look at the third example, as it demonstrates nicely how one can make theoreticaldivision of a claim in two parts, and it resembles the Nestec-Dualit case most.
“Let us assume that a first priority document discloses a method of coating the inner wall of a pipe and that a second priority document discloses the use of the same method for coating the inner wall of bottles or any other hollow bodies. If multiple priorities for one and the same claim are allowed, it will suffice in the European patent application to draw up a claim to a method for coating the inner wall of hollow bodies. If multiple priorities for one and the same claim are not allowed, the applicant will have to draw up two parallel claims, one directed to a method of coating the inner wall of pipes, which claim will enjoy the first priority, and a second claim directed to a method of coating the inner wall of hollow bodies not being pipes, which claim would enjoy the second priority.”
By now, we know what the authors of the memorandum did not know yet: multiple priorities for one and the same claim are allowed. As a consequence, it is not necessary to draw two claims, but one claim suffices. Moreover, this claim can theoretically be divided into two parts: one part covering a method of coating the inner wall of pipes, which part enjoys the first priority, and a second part covering a method of coating the inner wall of hollow bodies not being pipes, which part enjoys the second priority.
We conclude that “claiming of a limited number of clearly defined alternative subject matters” does not mean that the actual claim of the subsequent application itself defines these subject matters. Rather, it suffices that the priority documents define these alternative subject matters.
So what does the “provided…” of G2/98 then mean? Well, one could construe an example with many priorities, for instance six , all having a different claim 1, ending in a generic claim 1 having an inextricable mix of subject matters with their own priority dates. In such a case, legal certainty would be at stake, because it would become impossible to clearly divide the subject matter of claim 1 in a limited number of clearly defined alternatives, each having its own priority date. Such an example is not covered in the memo and may have been the concern of G2/98.It is clear that several judges and Boards of Appeal look upon this matter in a different way.
However, Tufty is not alone. In the discussion following our previous post, several authors have given their support to Tufty’s Law. Moreover, attention has been drawn to T 1222/11 which under reason 11.5 appears to support this interpretation too. Accordingly, we call upon the President of the EPO to refer a question to the Enlarged Board of Appeal to ensure uniform application of the law, and make Tufty’s law established EPO case law. We also call upon the United Kingdom Supreme Court not to wait for the EPO, but to completely assess priority on its own.
We conclude that Tufty’s Law detoxicates the poisonous priority issues (and by the way the poisonous divisional issue). Having said that, the other solutions, such as a grace period, need no further attention. They may serve their own purpose, e.g. international harmonisation, but they are not necessary to cure poisonous priority.
