T 0086/03 (Hard-surface cleaning/PROCTER & GAMBLE) 28-06-2004

1. Main Request

1.1. Late filed document

1.1.1. The Appellant filed document (8) only two days before the oral proceedings at first instance and argued that this document had not to be considered as late filed since it had already been cited and discussed in the description of the patent in suit (page 2, lines 36 to 40).

It is established case law of the Boards of Appeal of the EPO that a document which is cited in the description of the patent in suit but has neither been cited by the Opponents within the time limit for filing an opposition in accordance with Article 99(1) EPC nor by the Patent Proprietor or by the Opposition Division cannot be considered automatically to be part of the opposition proceedings; such a document has thus to be considered as part of the opposition proceedings only if it represents the closest prior art for the evaluation of the inventive step of the claimed subject- matter (see T 541/98, unpublished in OJ EPO, point 2.1 of the reasons for the decision and T 536/88, OJ EPO 1992, 638, points 2.1 and 2.2 of the reasons for the decision).

In the present case the Appellant did not take document (8) as the starting point for evaluating inventive step. The Board notes also that the description of the patent in suit does not identify this document as the closest prior art or as being of any importance for the claimed invention. Furthermore, neither the Respondent nor the Opposition Division cited this document during the opposition proceedings when discussing the patentability of the claimed subject-matter.

The Board concludes, therefore, that document (8) cannot be considered to be part of the opposition proceedings only because it is cited in the description of the patent in suit.

1.1.2. The Appellant did not bring any excuse for the late filing of document (8).

It remains thus to be decided if the Opposition Division was right in not admitting this document by making use of the provisions of Article 114(2) EPC.

It is established case law of the Boards of Appeal of the EPO that late filed evidence should only be admitted at the opposition or at the appeal stage if it can be considered at first sight to be more relevant than the evidence previously relied upon and to be prejudicial to the maintenance of the patent (see, e.g. T 1002/92, OJ EPO 1995, 605, points 3.3, 3.4 and 3.5 of the reasons).

The Appellant agreed that none of the examples of document (8) describes a product or a process as claimed in the patent in suit but put forward that the whole teaching of this document, combined with the common general knowledge about the use of diluted compositions in this technical field, would at first sight anticipate the claimed subject-matter (see e.g. page 5, lines 20 to 28; page 14, lines 9 to 25; page 9, lines 15 to 17; example 2h-l, in particular page 21, lines 26 to 29).

The Board finds, however, that even the particularly preferred concentrated compositions of document (8), i.e. those disclosed on page 14, lines 9 to 25, can comprise polymers which do not fall under the wording of the claims of the patent in suit, e.g. all copolymers based on combinations with ethylene, styrene, methyl vinyl ether and methacrylic monomers. Moreover, these compositions can have a pH in the range of 3 to 6, wherein a pH of e.g. 3 would appear not to give a pH within the range of the claims of the patent in suit even after dilution at the rate suggested in the examples 2h-l (page 21, lines 26 to 29). The Appellant has also not produced any evidence to the contrary. Furthermore, document (8) suggests as a general teaching that the disclosed compositions can be used in concentrated or diluted form (page 9, lines 11 to 17).

Therefore, the Board finds that, in order to arrive at the subject-matter of claim 1, the skilled person would have to perform various selections, i.e. he would have to select from the broader teaching of document (8) at least a polymer of the type used in the patent in suit, a pH near the upper limit of the suggested range in order to guarantee a pH of at least 6 after dilution and would have to decide to use such a composition in diluted form.

Document (8) thus does not disclose all the features of claims 1 or 4 of the patent in suit in combination.

The Board concludes that document (8) cannot be considered to be at first sight an anticipation of the claimed subject-matter.

1.1.3. Since the Appellant did not argue that this document would be more relevant than the other cited documents in regard to inventive step, the Board concludes that document (8) cannot be considered to be at first sight more relevant than the other documents cited by the Appellant or prejudicial to the maintenance of the patent in suit.

Therefore the Opposition Division was correct in not admitting this document under Article 114(2) EPC and, for the same reasons, it has not to be admitted into the appeal proceedings.

1.2. Novelty

Novelty of the claimed subject-matter was not disputed by the Appellant on the basis of the other cited documents (see point II above).

The Board has thus no reason to depart in this respect from the decision of the first instance that the claimed subject-matter is novel.

1.3. Inventive step

1.3.1. The patent in suit and, in particular, the subject- matters of claims 4 and 1 relate, respectively, to a hard surface liquid cleaning composition having a pH of from 6 to 13, comprising a specific carboxylate-containing polymer, a divalent counterion, added in the form of a non-complex salt or as one ingredient with said carboxylate-containing polymer at a specific molar ratio to said polymer and from 0.1% to 50% by weight of the total composition of a surfactant, and to a process of cleaning a hard surface by means of such a composition or of a dilution thereof (see page 2, line 5 and page 3, lines 20 to 46).

As explained in the patent in suit, there existed in the prior art hard surface cleaning compositions able to clean a hard surface without leaving a visible residue after use on the treated surface (so-called "streak-free" compositions) and products able to deliver gloss to a surface, e.g. by means of the use of silicones, but not providing efficient cleaning (see page 2, lines 9 to 20).

The technical problem underlying the patent in suit is therefore defined in the description of the patent in suit as the formulation of a hard surface liquid composition having excellent cleaning performance and providing a better gloss and less surface streaking when used in concentrated and diluted form (see page 2, lines 21 to 31).

The Appellant argued that by using "streak-free" compositions, which leave by definition no visible residues on the treated surface, the original gloss of the treated surface would be necessarily at least partially restored. Therefore, the technical problem of providing a composition able to restore the gloss of a treated surface would not be different from that of providing a "streak-free" cleaning composition.

The Board agrees that a "streak-free" cleaning composition could at least partially restore under certain circumstances the original gloss of a treated surface; however, the patent in suit pointed explicitly to the difference between the provision of gloss to a cleaned surface and a "streak-free" cleaning method (page 2, lines 13 to 15).

Since the gloss depends, as explained in the patent in suit, on the reflectance of light from the cleaned surface (page 2, lines 14 to 15), a "streak-free" cleaning composition, though not providing visible residues, could still provide not visible residues negatively affecting the gloss of the treated surface.

Therefore, the Board finds that the technical problem addressed in the patent in suit differs from the simple provision of a "streak-free" cleaning composition insofar as it strives at the purposive delivering of an improved gloss to the treated surface.

The Board concludes thus that the technical problem identified in the patent in suit is different from that of providing only a "streak-free" composition.

1.3.2. As agreed upon by all the parties, document (5) deals only with the provision of a "streak-free" hard surface cleaning composition and does not mention the improvement or even the restoring of the gloss of the treated surface (see page 1, lines 1 to 6).

Therefore, the Board finds that this document cannot be considered to represent the most suitable starting point for the assessment of inventive step.

Documents (6) and (7), which are similar in content, deal both with the cleaning of a hard surface and with the provision of improved gloss to the treated surfaces (see document (6), page 1, lines 1 to 10 and page 2, lines 27 to 32 and document (7) page 1, line 1 to page 2, line 5). Even though these documents suggest that the gloss is imparted rather by a layer deposited onto the surface than by restoring the original gloss of the treated surface (see previously cited passages), the Board finds that the patent in suit does not explain how the gloss is delivered to the treated surface and thus does not exclude that a layer providing gloss be formed on the treated surface. Therefore, these documents deal in the Board's finding with the same technical problem addressed to in the patent in suit.

As suggested by the Respondent, document (7) teaches that the gloss of the treated surface is improved only by using concentrated compositions and not by using diluted ones (page 2, lines 26 to 30) whilst this does not appear to be the case with the compositions of document (6) (page 3, lines 34 to page 4, line 6).

Therefore, the Board takes document (6) as the most suitable starting point for the evaluation of inventive step of the claimed subject-matter.

1.3.3. All the parties agreed that document (6) discloses a composition having a pH and a surfactant as required by the patent in suit, comprising a similar carboxylate-containing polymer and a divalent metal ion which is, however, added as a complex with volatile ligands, which complex can also be formed in situ. The molar ratio of polymer to divalent ion is also in accordance with the patent in suit (page 3, lines 11 to 28; table on pages 6 and 7; page 8, lines 1 to 13; page 9, lines 5 to 14).

The subject-matter of document (6) differs thus from that of the patent in suit only insofar as it involves the use of a complex of the divalent ions.

The Appellant argued during oral proceedings that the patent in suit could also involve the use of complexes of divalent ions similar to those used in document (6) since it involves e.g. the use of ammonium salts of surfactants (page 6, line 16) which could react in situ with divalent ions to form such a complex.

The Board finds that the Appellant did not bring any evidence that a metal complex could be formed during the preparation of a composition according to the patent in suit and that such compositions would be anyway not encompassed by the wording of the claims of the patent in suit requiring the presence of a divalent counter-ion in the form of a non-complex salt or as one ingredient with the polymer.

On the contrary, document (6) requires that the divalent ion is present in the cleaning composition as a complex, i.e. coordinated to ligands and, in regard to the formation of the metal complex in situ, is added as a compound which would react with the ligands to form the complex (see page 8, line 23 to page 9, line 14).

1.3.4. The technical problem underlying the claimed invention in the light of the teaching of document (6), can thus be formulated as identified in the description of the patent in suit (see point 1.3.1 above) as the formulation of a hard surface liquid composition having excellent cleaning performance and providing an improved gloss and less surface streaking when used both in concentrated or in diluted form.

The Respondent provided at first instance under cover of the letter dated 8 October 2002 comparative data showing that a composition in accordance with the patent in suit provides both in concentrated and in diluted form a better gloss to the treated surface than a similar composition comprising the preferred type of metal complex used in document (6) (page 9, line 7).

The Appellant argued that these tests were not relevant since the gloss of the treated surface was not completely restored and that therefore the cleaning operation amounted just to a "streak-free" cleaning.

The Board agrees that the original gloss of the treated surface is not completely restored in such experiments. However, this is not a requirement of the technical problem underlying the claimed invention and a conventional "streak-free" cleaning does not necessarily imply any restoring of the gloss as explained in point 1.3.1 above.

Since the contested experimental data show that the compositions of the patent in suit provide an improved gloss than prior art compositions comprising a metal complex of the type preferred in document (6), the Board concludes that the technical problem underlying the patent in suit has been convincingly solved by means of the claimed invention.

1.3.5. In the Board's judgement the skilled person would not have combined, in the absence of any explicit suggestion to do so, the teaching of document (6), relating to the delivery of gloss to a treated surface by means of a composition comprising a complex of a divalent metal as an ingredient responsible for the effect, with that of document (5) which referred to the more simple technical problem, i.e. that of providing "streak-free" cleaning compositions which did not comprise metal complexes.

The skilled person would thus not have found any incentive in the prior art for replacing the complex of divalent ions used in document (6) with a divalent ion salt, as used e.g. in document (5), with the expectation of providing improved gloss to the treated surface.

The Board concludes, therefore, that the claimed subject-matter involves an inventive step and thus meets the requirements of Article 56 EPC.