Partial opposition

Generally, opposition proceedings are an all-out war, and only the death of the patent can fully satisfy the opponent. But in rare occasions, one may come across an opponent who turns out to be less bloodthirsty, as in the recent case T 1264/12.

On the one hand, this decision is quite underwhelming, as the “reasons” section is remarkably short. But on the other hand, it seems interesting to have a closer look at the case, as it provides a rare example of a partial opposition.

The patent at stake is EP 1625093, owned by Bluestar Silicones France. In its granted version, the patent contains 21 claims.

Claim 1 is directed to a method of draining a flexible container containing a viscous product. Claims 2 to 10 depend on claim 1. Claim 11 is directed to a kit for carrying out the method according to any one of Claims 1 to 10. And claims 12 to 21 depend on claim 11.

The patent was opposed by a Finnish company named Oy Fluid-Bag Ab.

Rather unusually, the opposition only concerned claims 1-3, 8-13 and 21. As a side note, the opposition was filed in 2008, for a final decision issued 8 years later. This means that a partial opposition does not mean a speedy one…

Looking more closely at the claim structure in the patent, the following can be noted:

  • Method claims 4-6, which were unopposed, depend on claims 1-3 and form a group in which use is made of a draining device which notably comprises a pressure member having a piston, and a drainage vessel.
  • Method claim 7, which was likewise unopposed, also depends on claims 1-3 and forms another group of its own, in which use is made of a draining device which notably comprises at least one pressurizable drainage vessel, which is pressurized by means of a pressure fluid.
  • Method claim 8, which was opposed, also depends on claims 1-3 and forms another group of its own, in which use is made of a draining device comprising a pressure member having at least one roller and one counter-roller element.
  • Method claims 9-10, which were opposed, depend on claims 2-8 and are therefore relevant for the various groups mentioned above.
  • A similar structure applies to the kit claims. In particular, claims 14-16 (unopposed) depend on claims 11-13 and calls for a piston and a drainage vessel; claim 17 (unopposed) recites a pressurizable drainage vessel; and claim 21 (opposed) depends on claims 11-13 and notably recites a roller and a counter-roller element.

In summary, the patent seems to relate to three mutually exclusive embodiments, which I would call the piston embodiment, the pressurizable vessel embodiment, and the roller embodiment. Some claims apply to all three embodiments, while others apply specifically to one of those. It seems that only those claims which are relevant for the roller embodiment were opposed.

A roller (coaster) embodiment.
A roller (coaster) embodiment.

This is in fact confirmed by a helpful indication in the statement of facts and arguments of the opposition: “the opponent reserves the right to raise an objection against the claims if amended, on the basis of the description, to any such form that the draining of the container using roller(s) (corresponding to Figure 3 of the opposed patent) is readable from the claims“.

It seems that the opponent was not prepared to spend time and resources to challenge other embodiments than the one which obviously was of interest to them – which makes perfect sense. As a side note, in some cases it may even be beneficial for an opponent if a patent partially survives and lies in the way of third party competitors who may be interested in further technical solutions.

In first instance, the patent was maintained in amended form. But the amendment was apparently not good enough for Oy Fluid-Bag, who filed an appeal.

According to the appeal decision, the sole request of the patentee on file contained four independent claims:

  • One method claim corresponding to the combination of claims 1, 2, 4 and 9 as granted.
  • Another method claim corresponding to the combination of claims 1, 2, 7 and 9 as granted.
  • One kit claim corresponding to the combination of claims 11 and 14 as granted.
  • Another kit claim corresponding to the combination of claims 11 and 17 as granted.

In other terms, the patent was restricted to the piston embodiment and the pressurizable vessel embodiment. The roller embodiment was no longer covered.

The appeal decision, which as I said is very short, does not explain why these amendments were introduced. In order to understand what happened, we need to review the minutes of the oral proceedings.

It turns out that the main request of the patentee was originally that the appeal should be rejected and thus that the patent be maintained in the same form as in first instance. However, the Board found that kit claim 9 of this main request lacked inventive step.

An auxiliary request No.2 was then discussed, but kit claim 9 of this request was also found to lack inventive step.

At this point, the patentee had to fall back on auxiliary request No.3, restricted to the piston and pressurizable vessel embodiments. The appellant objected that one of the product claims was not fully clearly restricted to these embodiments, and the patentee thus filed an amended request on the spot to overcome the issue. This new request was admitted into the proceedings.

Then, the patentee withdrew all the other requests, presumably so as to avoid any negative statement from the Board in the written decision on some of the granted claims. This is why the decision is so short and focuses on the roller embodiment-only request.

Now, here (finally) comes the Board’s assessment of this final request, in my own unofficial translation:

Since the extent of the opposition is limited to claims 1-3, 8-13 and 21 of the patent as granted, the claim combinations mentioned above result in claimed subject-matter which was not challenged by the opposition (rule 76(2)(c) EPC). 

The subject-matter of the above-mentioned claims are not the subject of the opposition (see in this respect G 9/91 (OJ 1993, 408), item 10 of the reasons) and there is no procedure under articles 114 and 115 EPC relating to these non-challenged elements. Therefore, the Board has absolutely no power to rule on them, which also necessarily applies to claims which include their subject-matter.

The appellant confirmed this position of the Board during the oral proceedings. The Board can only maintain the patent with these claims (volenti non fit injuria). 

For the benefit of continental Europeans like me, the latter phrase seems to be not only a fancy display of Latin but also an actual legal concept under common law (albeit within a quite different context).

I do not doubt that the Board reached the correct decision in not reviewing the new main request.

That said, the founding decision G 9/91 quoted above does leave some room for examining claims other than those which were opposed.

The first sentence of the Enlarged Board’s headnote is the following:

The power of an Opposition Division or a Board of Appeal to examine and decide on the maintenance of a European patent under Articles 101 and 102 EPC depends upon the extent to which the patent is opposed in the notice of opposition pursuant to Rule 55(c) EPC.

But then the second sentence goes like:

However, subject-matters of claims depending on an independent claim, which falls in opposition or appeal proceedings, may be examined as to their patentability even if they have not been explicitly opposed, provided their validity is prima facie in doubt on the basis of already available information.

For instance, in T 525/96, only two process claims 13 and 14 were opposed. In an auxiliary request, these process claims were deleted, but a product-by-process claim, referring to the same process, remained. The Board examined whether this unopposed product-by-process claim was allowable, based on the above principles set forth in G 9/91, and came to a negative conclusion, leading to the rejection of the corresponding auxiliary request.

Therefore, the Board in T 1264/12 probably theoretically had the power to examine the unopposed piston embodiment and pressurizable vessel embodiment claims, if their validity was prima facie in doubt.

We can safely assume that this was not the case. In particular, the opponent had probably not submitted any prior art relevant with respect to other embodiments than the roller one which they were concerned with. Besides, the opponent apparently did not object to the third-auxiliary-turned-main request.

But strictly speaking, the absence of prima facie invalidity might be a missing step in the Board’s reasoning.


CASE REFERENCE: T 1264/12, Board of Appel 3.2.07, September 22, 2016, Oy Fluid-Bag Ab v. Bluestar Silicones France.