Wednesday, 30 December 2009

T 1120/05 – Deriving Negative Features from Drawings

Claim 1 of the main request concerned an arrangement for managing a herd of freely walking animals, comprising an area (1) for receiving the animals, a milking station (2) located in said area […], and a separation device (3) located in said area for separating an animal from the herd, wherein […]the separation device (3) comprises […] at least one entrance device (13) forming an animal passage (15) leading from the receiving area (1) to the separation zone (11), but not to the milking station (2) […].

The amendment “but not to the milking station (2)” introduces the negative feature that the passage formed by the entrance device of the separation device does not lead from the receiving area to the milking station. This negative feature is not expressly disclosed in the description and in the claims of the patent application as filed. [2.1]

According to the well established jurisprudence of the Boards of Appeal, features may be taken from the drawings if their structure and function are clearly, unmistakably and fully derivable from the drawings (see T 169/83). It goes without saying that it is not possible to derive a negative or missing feature on its own, i.e. without the context of the other, existing features of the claim. It remains to be decided if a combination of features including the negative feature can be derived or not. [2.2]

This approach accepts, arguendo, that the skilled person is actually capable of finding - and indeed willing to search for - negative features in a drawing, albeit in combination with some other features. In the present case the combined feature “[an animal passage (15)] leading from the receiving area (1) to the separation zone (11), but not to the milking station”, i.e. a feature which describes a property of the animal passage lends itself to closer scrutiny, because the term “..., but not to...” establishes a direct connection of the disputed negative feature to an other, undisputedly disclosed feature. An equally good candidate would be the combined feature “an animal passage (15) ... not [leading] to the milking station”. The search for combined features, such as the examples above may even be considered realistic, because there are also other features of this animal passage present in the claim. Therefore, in the present case the board accepts - for the sake of argument only - that the skilled person would look closely at the features related to the animal passage. [2.2.1]

In this case, the question arises whether the skilled person would clearly, unmistakeably and fully derive from the drawings that this animal passage has a further feature beside those explicitly stated in the application, i.e. whether the skilled person would positively realise that this animal passage does have some negative features as well. Were the board to accept that this is the case, then, as a matter of logic, the board would have to establish that the skilled person would, inevitably, realise the presence of further negative features, and potentially a large number thereof. Choosing arbitrarily one of these is not permitted, because the skilled person not only has to realise the possible negative features, but because they were derived from the drawings, he must also establish which one of the features is essential to the invention and which ones are not, see Guidelines, C VI. 3.5.2., see further T 906/97 [5]. The board finds that absent a teaching from the description, the skilled person would be unable establish the essential nature of a single negative feature, seen against a background of a multitude of potentially essential features, even if this selected single negative feature in the drawings could be recognised by the skilled person in the drawings. [2.2.2]

It may be mentioned that case law also confirms that negative features cannot be deduced from a schematic drawing only, see T 170/87 [8.3], followed by T 410/91 [2.1], further see T 278/88 [3.2.3].

[…] More generally, in the context of A 123(2) the original drawings cannot be considered as a reservoir of features from which the applicant or a patent proprietor can draw when amending the claims, see T 832/04 [2.2]. [2.2.3]

Decision T 169/83 requires that “the structure and function” of the negative feature should be clearly, unmistakeably and fully derivable for the skilled person from the drawings. This is not the case here. The represented separation device (3) is provided with an exit device forming an animal passage (15) leading from the separation zone and from here - at least indirectly through the receiving area - to the milking station. In this manner the drawings may also be interpreted as disclosing that the entrance devices of the separation device (3) define a passage leading from the receiving area to the milking station via the separation device (3), the animal passage (15) and the receiving area. It follows that at least the “structure” of the negative feature in question cannot be deduced, let alone be clearly, unmistakably and fully derived from the drawings. [2.2.4]

[…] The passage of the patent specification referred to by the [patentee] […] defines the result to be achieved by the invention, that is to avoid that the animal associates the separation with the automatic milking. However, this result does not necessarily imply the above mentioned negative feature. [2.2.6]

This negative feature therefore adds subject-matter extending beyond the content of the application as filed. Moreover, the board does not consider this undisclosed negative feature as being an allowable disclaimer in the meaning of decision G 1/03, because the anticipation necessitating the amendment (D4) cannot be considered as accidental. [2.3]

Therefore, the main request has to be rejected because [it] contravenes the requirements of A 123(2). [2.4] 

To read the whole decision, click here.