As a present to priority nerds, and probably a punishment to others, here is another post on the burning issue of partial priority.
In a previous post, I attempted to provide some practical tips to patent drafters anxious about the outcome of the referral to the Enlarged Board of Appeal on the issue of poisonous (or toxic, whichever you like best) divisionals. As was recalled in this post, the issue boils down to how partial priority is assessed: under what we could call a “broad” or “generous” interpretation of partial priority, any generalized claim can partly benefit from the priority of a partial original disclosure, and thus be immune to anticipation by any poisonous divisional, poisonous parent or any other poisonous you-name-it family member; if, however, one believes that partial priority requires certain specific conditions in order to be acknowledged (let’s call this the “narrow” or “strict” interpretation), then generalized claims which do not pass the test (whatever it is) may be prone to some kind of incestuous anticipation.
Several boards of appeal adopted the strict interpretation of partial priority, whereas Board 3.3.07 preferred the broad and generous interpretation, notably in decision T 1222/11. This is the divergence in case law which led to the referral to the Enlarged Board.
Today, I would like to focus on this decision T 1222/11 in more detail: not so much on the (very interesting) obiter part of the ruling where the Board discusses in detail why they believe the strict interpretation put forward by other boards is wrong; but rather on the rest of the decision, which should not be ignored and is very informative indeed.
Oh – and did I forget to mention it? In this ex parte case T 1222/11, the patent application died in the end. It did not die because of a toxic divisional though, as Board 3.3.07 does not believe in toxic divisionals – and as this was not an issue anyway. But it died all right, and because of an invalid priority claim.
With this in mind, is it possible that the broad and generous interpretation might not be so generous after all with applicants and patent proprietors? At any rate it is certainly worth having a closer look at what exactly went wrong in T 1222/11 for the applicant Kao Corporation, and how they were unfortunately K.O.-ed.
In the case at hand, the application claimed the priority of a Japanese patent application, and the text of the application as filed was identical to the English translation of this Japanese patent application (reasons, 7).
But there was also an earlier PCT application by the same applicant, D4b, with a similar disclosure. In particular, D4b included several examples falling within the scope of the claims of the application at stake.
According to Kao, since D4b was only intermediate prior art under Article 54(3) EPC, it was possible to introduce a disclaimer into the main claim, more precisely a G 1/03-type undisclosed disclaimer, so as to restore novelty over D4b. Various formulations for the disclaimer were put forward as a main request and auxiliary requests.
This line of defense by the applicant was based on the presupposition that the priority claim of the application was valid.
If however the priority claim was in fact invalid, then D4b became full prior art under Article 54(2) EPC, as a result of which the introduction of an undisclosed disclaimer to restore novelty over D4b was no longer permitted, in view of the conditions set forth in G 1/03.
This is why the Board examined the validity of the priority claim, focusing on the fact that
According to Article 87(1) EPC, a requirement for enjoying a right of priority for filing a European patent application is that the application for a patent […] on the basis of which the priority is claimed must be the first application in respect of the same invention (reasons, 7).
The Board therefore compared the teaching of the priority document with that of the earlier application D4b by the same applicant. The Board explained that, if the earlier application D4b related to the same invention as the Japanese priority document, then said Japanese priority document could not be considered as a “first application” and thus the priority claim was invalid.
As a side note, the applicant could not possibly rely on the mechanism of Article 87(4) EPC, per which
a subsequent application in respect of the same subject-matter as a previous first application and filed in or for the same State shall be considered as the first application for the purposes of determining priority, provided that, at the date of filing the subsequent application, the previous application has been withdrawn, abandoned or refused, without being open to public inspection and without leaving any rights outstanding, and has not served as a basis for claiming a right of priority.
Indeed, D4b had been published and (if only for this reason) could not be considered as having been merely replaced by the later Japanese application.
Let’s now go back to the comparison between the priority document (substantially identical to the application at stake) and the earlier application D4b. The priority document, just like the claimed invention itself, was directed to a leave-on hair cosmetic composition containing an organic dicarboxylic acid (A) and an organic solvent (B), and further characterized by a certain pH and a certain buffering capacity. The Board first of all noted that 6 examples of compositions in D4b fell within the scope of claim 1 – these were the formulations that the applicant tried to exclude from the application at stake by way of a disclaimer. In addition, there were many more similarities between the priority document and D4b, including in terms of preferred components.
Only the buffering capacity was not explicitly recited in D4b, but for the Board, this parameter was simply a consequence of the other technical features present in D4b.
This finding meant that the priority document related to the same invention as D4b – and therefore the priority claim was invalid.
One aspect was more particularly discussed by the applicant, namely the fact that D4b was limited to the use of a combination of malic acid and lactic acid as component (A), whereas the priority document and the claimed invention were not.
According to the Board, this
does not mean that D4b and the present application do not contain a common subject-matter or invention, but only means that the disclosure of D4b does not extend to the use of malic acid without any lactic acid. In other words, the present subject-matter can be seen as the invention of D4b supplemented with additional subject-matter relating to the use of malic acid without lactic acid (reasons, 9.4).
To put it differently, the priority document as well as the claimed invention were generalized relative to the subject-matter of the earlier application D4b.
But, despite such generalization, both the priority document / the application and D4b were found to relate to the same invention. This is made quite clear in the other following statements by the Board:
It follows from the above that the combination of features defined in positive terms in the first part of present claim 1 of the Main Request cannot be distinguished from the disclosure of the earlier application D4b. Example Products 10 to 14 and Example Product 6 of D4b constitute prior disclosures of the combination of features defined in positive terms in the first part of present claim 1 of the Main Request and therefore cannot be held to relate to a different subject-matter, i.e. a different invention (reasons, 9.2)
It must be concluded […] that the Appellants cannot benefit from the priority claimed for the combination of features defined in positive terms in amended claim 1, in so far as it covers subject-matter disclosed in D4b, in particular in so far as it covers the six compositions disclosed in D4b which the Appellants are seeking to disclaim (reasons, 10).
Further down in the decision, in the obiter dictum on partial priority, the Board explains that it is sufficient for the purpose of benefiting from partial priority if alternative subject-matters in a broad claim can be conceptually identified – a very undemanding requirement.
The Board further notes that this
also implies in view of the necessary coherence of rules of law on the subject of claiming priority defined in the EPC, that when an application on the basis of which a priority date is claimed encompasses a narrower subject-matter already disclosed by the same applicant in an earlier application, the decision on whether the claim to priority on the basis of the later application is valid does not depend on whether the narrower subject-matter disclosed in the earlier application is identified in said later application. The latter situation is precisely the one underlying the case under appeal (reasons, 11.8).
The bottom line of this rationale is that, when two successive applications are filed by a same applicant, the second one having a broader subject-matter than the first one, then the second application can never be used to claim priority for a (yet) subsequent filing – unless use is made of the special provisions of Article 87(4) EPC, i.e. the first application is nipped in the bud.
Logically, one should reach the opposite conclusion if the “narrow” interpretation of partial priority advocated by the other, poisonous divisionals-friendly boards, is used.
So, the “broad” interpretation may save a number of patents from the unpleasant agony of being poisoned by another member of their family; but it may also toll the bell for some applicants who like to file successive applications for relatively similar subject-matters, and possibly broaden the definition of their inventions over time, starting from specific examples.
Thus, whatever the outcome of the pending referral is, it seems that extreme caution will still be required for properly claiming priority.
CASE REFERENCE: Board of Appeal 3.3.07, T 1222/11, Kao Corporation, December 4, 2012