T 0108/91 (Lockable closure) of 17.9.1992

Summary of Facts and Submissions

I. The appellants are the proprietors of European patent No. 0 048 472 which was granted with effect from 15 January 1986 on the basis of European patent application No. 81 107 429.3 and revoked by a decision of the Opposition Division dated 20 September 1990, and issued in written form on 28 November 1990.

II. The patent had been opposed by the appellants themselves and by the respondents (Opponents 2 and 3) on the basis that its subject-matter lacked novelty and/or inventive step with respect to the state of the art (Article 100(a) EPC). The respondents also put forward the ground that the subject-matter of the patent extended beyond the content of the application as filed (Article 100(c) EPC).

The following state of the art was relied upon:

(D1) FR-A-2 377 333,

(D2) GB-A-1 438 136,

(D3) Information sheet "Superfos Container".

Prior use of the container-closure arrangements "H50/DH50" and "H100/DH100" manufactured by Opponent 3 (Saier).

III. In the contested decision it was held that the subject- matter of the amended main claim filed during the opposition proceedings lacked inventive step with respect in particular to the Saier container-closure arrangements, the public prior use of which had been acknowledged by the appellants.

IV. An appeal against this decision was filed on 25 January 1991, the appeal fee being paid on the same day.

The statement of grounds of appeal, accompanied by a new main claim, was received on 30 March 1991.

V. In a communication of the Board dated 7 April 1992 pursuant to Article 11(2) RPBA (Rules of Procedure of the Boards of Appeal) various objections to the new claim filed with the statement of grounds were made under Articles 84 and 123 EPC. As far as the assessment of inventive step was concerned it was indicated that the arrangement shown in Figures 20 and 21 of document D2 would seem to represent the most appropriate starting point.

VI. Oral proceedings were held on 17 September 1992. At the oral proceedings the appellants submitted a new Claim 1 on the basis of which maintenance of the patent was requested. This claim is worded as follows:

"A container-closure arrangement comprising a container (11) and a closure (10, 50, 60, 70) for closing the opening of the container (11), said opening being limited by a wall (13) of the container (11), said wall of the container including a circumferential and outwardly disposed annular projection (12), the closure (10, 50, 60, 70) including at least one essentially annular portion (14) adapted to contact a portion (15) of the annular projection (12) of the container (11) and including a circumferential extension (18, 51, 53, 71, 72) adapted to be moved in relation to said annular portion (14) of the closure (10, 50, 60, 70), shoulder means (16, 52) being adapted to pivot about the annular projection (12) of the container (11), said shoulder means (16, 52) being integral with and extending from said annular portion (14) of said closure (10, 50, 60, 70), said shoulder means (16, 52) being movable into and out of locking engagement with the annular projection (12) of the container (11), said circumferential extension (18, 51, 53, 71, 72) forming deflectable bending means being integral with and extending from said shoulder means (16, 52) said deflectable bending means (18, 51, 53, 71, 72) co-operating with said shoulder means (16, 52) to provide a mechanical leverage system (12/14/15, 52/18, 51, 53, 71, 72) for pivoting said shoulder means (16, 52) about the annular projection (12) of the container (11), said mechanical leverage system being adapted to move said shoulder means (16, 52) into and out of locking engagement with the extended end of the annular projection (12) of the container (11), said deflectable bending means (18, 51, 53, 71, 72) including an annular continuous portion normally retaining said shoulder means (16, 52) in either an unlocked or locked position out of or in engagement with the annular projection (15) of the wall of the container (11), characterized in that the circumferential and outwardly disposed annular projection (12) is a downwardly extending lip, that said mechanical leverage system (12/14/15, 52/81, 51, 53, 71, 72) is arranged and adapted for pivoting said shoulder means (16, 52) about the end of said downwardly extending lip (12), the area of pivoting being where said shoulder means extends from said annular portion, from an upper, unstressed, unlocked position to a lower, locked position, as said bending means (18) is deflected from its upper, unstressed, unlocked position to its lower, unstressed, locked position, and that the shoulder means (16) is retained in a locked position in engagement with the annular lip (12)."

As an auxiliary request the appellants proposed clarifying the claim of the main request in the sense that contact between the shoulder means and the end of the downwardly extending lip was defined.

VII. The arguments of the appellants in support of their requests can be summarised as follows:

A. It was clear from a reading of the patent specification as a whole that an essential feature of the invention was the movement of the deflectable bending means between two stable unstressed positions, in the first of which the closure was unlocked and in the second locked, by virtue of the shoulder means, to the container. In the course of the examination proceedings the second, locked, position had unfortunately been referred to in terms of a substantially unstressed position of the shoulder means rather than the deflectable bending means.

It was however evident from the patent specification that the shoulder means themselves were not unstressed in the locked position since in those embodiments where the shoulder means were constituted by a continuous annulus this annulus had a smaller diameter in the locked position than in the unlocked position and must therefore be under hoop compression stress, and in all embodiments there was a reaction stress in the shoulder means due to the closure being pulled down onto the annular projection of the container.

Claim 1 had now been amended to remedy the poor choice of words made in the examination proceedings and accurately to reflect what was actually disclosed in the patent specification and the application documents as originally filed. Such an amendment did not contravene Article 123(3) EPC as the extent of protection conferred by a claim was not determined by the strict, literal meaning of its wording. ...

VIII. The arguments of the respondents in reply can be summarised as follows:

A. The statement in granted Claim 1 that the shoulder means were retained in a substantially unstressed locked position imposed an unequivocal and technically meaningful restriction on the extent of protection conferred by the claim. The deletion of this feature therefore contravened the requirement of Article 123(3) EPC and could not be allowed. ...

In view of the above the respondents requested that the appeal be dismissed.

Reasons for the Decision

1. The appeal complies with the requirements of Articles 106 to 108 and Rules 1(1) and 64 EPC; it is therefore admissible.

2. Admissibility of amended Claim 1

2.1 In order to facilitate an understanding of the import of the proposed amendments it is necessary first of all to discuss briefly how the container-closure arrangement disclosed is structured and functions.

The closure is formed adjacent its rim with a downwardly facing annular channel which receives the rim of the container, the latter being formed with an outwardly and downwardly extending annular lip. The outermost section of the annular channel, the "shoulder means" in the terms of Claim 1, is joined via an area preferably of reduced thickness to the body of the closure, this area acting as an integral hinge which allows pivoting of the outermost section of the channel about the end of the downwardly extending lip of the container. This pivoting is effected by means of a frusto-conical ring, the "deflectable bending means" of Claim 1, which extends from the outermost section of the annular channel or shoulder means and which can be snapped over from an upwardly facing position, where the closure is free for removal from the container, and a downwardly facing position, where the closure is locked by the outermost section of the annular channel onto the container.

2.2 It is clearly expressed in the original disclosure that the deflectable bending means are unstressed in both the locked and unlocked positions thereof. On the other hand there is nothing in the original disclosure which specifically suggests that the shoulder means are also unstressed in their locked position. Indeed, having regard to the technical considerations involved, this cannot be the case. Thus, in the majority of the embodiments disclosed the shoulder means are constituted by a continuous annulus which in its locked position has a smaller diameter than in its unlocked position. This annulus must therefore be under a hoop compression stress in the locked position. Furthermore, and this applies to all embodiments disclosed, it would run against the implicit technical objective of firmly securing the closure to the container if the shoulder means were not under some stress through their engagement with the end of the lip of the container.

Accordingly it can be seen that the feature included in Claim 1 by amendment during the examination proceedings that "the shoulder means is retained in a substantially unstressed locked position in engagement with the annular lip" effectively describes a container-closure arrangement which although technically feasible in itself does not actually correspond to what was disclosed. This amendment consequently offended against the requirement of Article 123(2) EPC that an application may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.

2.3 The wording of Article 123(2) EPC is reflected in Article 100(c) EPC according to which it is a ground of opposition that the subject-matter of the patent extends beyond the content of the application as filed.

It has been established above that the statement in granted Claim 1 that the shoulder means is substantially unstressed in its locked position is not derivable from the original disclosure, so that the ground of opposition under Article 100(c) would hold good against any claim in which this feature was retained. On the other hand deletion of this statement would at least at first sight appear to run foul of Article 123(3) EPC according to which the claims of the patent may not be amended during opposition proceedings in such a way as to extend the protection conferred.

A number of earlier decisions of the Boards of Appeal have considered what has been termed the "conflict" between the provisions of Articles 123(2) and (3) EPC but which, having regard to what is said above, can perhaps be more accurately described as the impasse created by the combined operation of Articles 100(c) and 123(3) EPC.

In Decision T 231/89, OJ EPO 1993, 13, it was found that the offending feature in granted Claim 1, i.e. that a torsion spring was "flat", was devoid of technical meaning in its context, did not therefore in fact impose any limitation on the extent of the protection conferred by the claim, and could accordingly be deleted without infringing Article 123(3) EPC.

The offending feature considered in Decision T 938/90 of 25 March 1992, not to be published, which was the temperature at which a melt viscosity was determined, was however considered to be essential to an adequate definition of the claimed invention, the introduction of this feature during examination proceedings having been necessary to overcome an objection of insufficiency under Article 83 EPC. Accordingly, deletion of the feature was not allowed and the decision of the Opposition Division to revoke the patent on the ground of opposition under Article 100(c) EPC was confirmed.

The present case differs significantly from both of the situations considered above, which may be thought of as marking the ends of the spectrum of type of inadmissible amendment made during examination proceedings. On the one hand it cannot be said that the statement in granted Claim 1 of the contested patent that the shoulder means is retained in a substantially unstressed locked position is technically meaningless in the context of the claim, indeed as indicated above, the skilled man would not on a reading of the claim alone have reason to doubt that the container-closure arrangement set out there was a technically feasible construction, although he would perhaps ask himself why the unstressed locked position was desirable. On the other hand there is no suggestion that the feature involved was included in any way to remedy a deficiency of insufficiency or that the attribution of the unstressed condition to the shoulder means was essential for the assessment of novelty or inventive step. The latter is evident from the fact that the offending amendment of Claim 1 occurred while attempting to put the claim into a proper two-part form after the Examining Division had already indicated that its subject-matter was patentable.

It must also be noted that in Claim 1 according to the requests of the appellants the offending feature has not simply been deleted but has been replaced in effect by the feature that the bending means are unstressed in their lower, locked position. In other words an inaccurate technical statement in granted Claim 1, which is evidently inconsistent with the totality of the disclosure of the patent, has been replaced by an accurate statement of the technical features involved.

The Board takes the view that this amendment does not infringe Article 123(3) EPC. This follows from a consideration of Article 69(1) EPC and the associated Protocol on its interpretation which set out the way in which the extent of protection conferred by a patent is to be determined, in particular how the description and drawings of the patent should be drawn upon to interpret the claims. In the present case it becomes immediately apparent, once recourse is had to the description and drawings of the patent specification, that what is defined in granted Claim 1 could not be that for which protection was sought and that the intended meaning must have been the equivalent of what is stated in this respect in the amended claim. In other words, on a fair interpretation of the claim in the light of the totality of disclosure of the patent the protection conferred by it has not in fact been extended.

2.4 This approach to the admissibility of a broadening amendment to a granted claim concurs in principle with that taken in an earlier decision of this Board, T 371/88, OJ EPO 1992, 157, in which the deletion of a feature from granted Claim 1 which excluded one of the embodiments disclosed was allowed. In the present case, as is apparent from what is said above, the offending feature in granted Claim 1 effectively excluded not one but all of the embodiments disclosed.

2.5 The amended Claim 1 according to the main and auxiliary requests of the appellants is also not open to any objection under Article 123(2) EPC as its features can all be derived from the original disclosure, particularly when reference is made to the drawings. Since the admissibility of amended Claim 1 in this respect was not disputed by the respondents further detailed explanations on this point are unnecessary.

3. Novelty and inventive step

Accordingly, the Board comes to the conclusion that the subject-matter of Claim 1 according to the main and auxiliary requests of the appellants lacks inventive step (Article 56 EPC).

3.3 In these circumstances the subject-matter of dependent Claims 2 to 11 need not be considered.

ORDER

For these reasons it is decided that:

The appeal is dismissed.