The patent relates to an Al-Zn-coated steel sheet that exhibits excellent corrosion resistance after painting.
Brief outline of the case
Claim 1 as granted was lacking N over D4=EP 2 957 648, prior art under Art 54(3) which was not mentioned in the SESR.
The patent was maintained in amended form according to AR1.
The opponent and the proprietor appealed the decision. The proprietor later withdrew its appeal.
The board dismissed the opponent’s appeal.
The case is interesting in view of the disclaimer introduced in claim 1 of AR1.
Claim 1 of AR 1
Claim 1 of AR 1 as held allowable by the opposition division reads
An Al-Zn-coated steel sheet comprising: ……
with the proviso that the Al-Zn-coated steel sheet is not a hot-dip Al-Zn alloy coated steel sheet according to Table 1 below and having a spangle size and Vickers Hardness as given in Table 1 below;
the hot-dip Al-Zn alloy coated steel sheet according to Table 1 below having a cold rolled steel sheet as a base steel sheet with a thickness of 0.35 mm produced by a conventional method;……..
The opponent’s point of view
Objections under Art 123(2)
The opponent considers that the undisclosed disclaimer introduced in claim 1 removes more than necessary to restore N, contrary to the conditions for drafting a disclaimer developed in point 3 of the reasons of G1/03, see headnote 2.2.
Objections under Art 84
The clarity of the disclaimer in claim 1 had to be evaluated while considering what the skilled person would have understood in reading the claim only, taking into consideration common general knowledge. The disclosure of D4 had to be disregarded when interpreting the disclaimer in claim 1.
The wording of the disclaimer was unclear because the expressions “produced by a conventional method” and “top roll” were unclear and undefined. It was further confirmed by case law that the term “conventional” was unclear. There was no information on what a “conventional method” implied on the corresponding base steel sheet and how such a base steel sheet differed from a base steel sheet obtained by a “non-conventional method”.
The wording of the disclaimer was further unclear since neither claim 1 nor the corresponding description specified the methods to measure the spangle size value and the Vickers hardness value. The values for these parameters were meaningless in the absence of a specification of the measuring conditions
Objections under Art 83
The skilled person was unable to carry out the invention in view of the spangle size value and the Vickers hardness value specified in the disclaimer, for which no measurement methods were specified in the patent.
The proprietor’s point of view
Objections under Art 84
The clarity of the wording of the disclaimer in claim 1 had to be assessed with a mind willing to understand, not a mind desirous of misunderstanding.
Defining the Vicker’s hardness and spangle size in line with the disclaimer based on D4 did not render claim 1 unclear. Amended paragraph  of the patent stated that “Example 15 of PTL 7 is disclaimed“. The conditions for measuring the Vicker’s hardness and spangle size defined in the disclaimer of claim 1 were clear for the skilled person, since the skilled person knew from paragraphs  and  of D4, to which amended paragraph  of the patent refers, which measurements methods should be used.
Objections under Art 83
There was no dispute in the appeal procedure that the invention according to claim 1 as granted was sufficiently disclosed by the patent. Claim 1 of AR 1 merely gave up a small amount of the original monopoly, i.e., the hot-dip Al-Zn alloy coated steel sheet according to Example 15 of D4.
The introduction of a disclaimer however did not render the description of the patent insufficient. The opponent had not presented verifiable facts that could generate doubts concerning the sufficiency of disclosure.
The board’s position
Objections under Art 123(2)
Example 15 of D4 describes a specific composition for the coating, see Table 1.1. Although Example 15 describes a Al-Zn plated steel sheet, it does not specify the content of Zn in the plating.
Neither the disclosure regarding Example 15 of D4 nor the corresponding disclaimer thus exclude the possibility that the upper layer of the coating comprises a relatively high content of e.g. Ni and/or a relatively low amount of Zn.
Although D4 defines in preferred embodiments according to claims 3 and 8 that certain elements can be present in a total amount of up to 10 wt.-%, this limitation is neither defined in claim 1 nor disclosed in Example 15 of D4.
Since the balance of the Zn-Al coating is neither defined in Example 15 of D4 nor in the disclaimer of claim 1, the disclaimer provides the same level of generality as Example 15 of D4 regarding the composition of the balance.
Hence, the disclaimer according to claim 1 does not remove more than is required by the disclosure of D4 regarding the composition of the upper layer.
The disclaimed coated steel sheet has inevitably also the corrosion resistance properties as the coated steel sheet according to Example 15 of D4.
Objections under Art 84
The skilled person consistently interprets the same wording in the same technical context, i.e. Al-Zn plated steel sheets. Hence, if the skilled person is able to determine directly and unambiguously what was disclosed in Example 15 of D4 for the assessment of novelty, the skilled person is also capable to determine what is defined by the wording of the corresponding disclaimer in claim 1 of AR 1. The disclaimer precisely reflects the wording of Example 15 of D4 and which thus does not reshape the claims arbitrarily in the sense of G1/03, reasons 3.
Although claim 1 does not define what should be considered a conventional method, the skilled person would interpret the term “conventional” in the context of claim 1. A skilled person dealing with the galvanisation of steel sheets has no difficulty in determining what is meant by “a cold rolled steel sheet […] produced by a conventional method”, since cold rolled steel sheets have been manufactured for decades and the method of manufacturing has no relevance for such conventionally manufactured steel sheets, in particular in the context of hot-dip coating thereof.
Hence, the board was of the opinion that in the context of claim 1, the term “conventional” may well be broad but it is not unclear.
For the present board, there is no general rule that in order to meet the requirements of Art 84 a claim itself needs to define the measurement methods. They can alternatively be specified in the description. This was per se not contested by the opponent who argued, however, that the measurement method needs to be specified in the description of the patent itself. A reference to a further document in the description, in particular to the one on which the disclaimer is based, is not enough.
However, in the present case, amended paragraph  of the description explicitly mentions that Example 15 of D4 (“Patent Literature” PTL 7) is disclaimed. This statement in paragraph  on the one hand provides transparency with regard to the basis for the amendment to the patent as granted, i.e. the introduction of an undisclosed disclaimer, in line with the requirements for formulating a disclaimer as set out in the last paragraph of point 3 of the reasons of G1/03. At the same time, the statement provides transparency concerning the parameters referred to in the disclaimer of claim 1.
Hence, it is clear for the skilled person that the parameters referred to in the disclaimer are measured by the methods indicated in D4, paragraphs  and . In this context, the Board does not follow the opponent’s opinion, that the disclosure of D4 (although specifically referred to in the patent as basis for the disclaimer) would be ignored by the skilled person.
Thus, although different methods for measuring the spangle size and the Vickers hardness may exist as taught by D12 and D13, the skilled person nevertheless is not left in doubt by the patent which measurement methods should be used.
The Board concluded that claim 1 of AR1 fulfils the requirements of Art 84.
Objections under Art 83
As discussed above, the board takes the view that the conditions for performing Example 15 of D4 have been introduced in the contested patent, see amended paragraph  (“Example 15 of PTL 7 is disclaimed”), the same way as the disclaimer in claim 1. As a consequence, the fact that different measurements methods could be available elsewhere (e.g. D12 or D13) is not decisive. The skilled person would immediately and directly refer to the methods which are disclosed in D4, paragraphs  and  due to the reference in paragraph  of the patent.
The Board concluded that claim 1 of AR1 fulfils the requirements of Art 83.
Drafting of disclaimers is always a rather arduous task.
The opponent has a point when he considers that the disclosure of D4 has to be disregarded when interpreting the disclaimer in claim 1. If, in principle, the description of a patent is not to be taken into account when interpreting a claim, this must apply as well to the description of a document leading to a disclaimer.
Whether a disclaimer gives up a small amount of the original monopoly or a large chunk of it is actually irrelevant.
A possible message from the decision is the following: a disclaimer is allowable under Art 123(2) provided it disclaims the teaching disclosed in a piece of prior art under Art 54(3), even if this teaching might appear general, but collides with the similar general teaching of an application/patent under scrutiny.
Contradiction with existing case law – method of measurement should in principle be in the claim
In its decision, Reasons 3.4.6, the board asseted that there is no general rule that in order to meet the requirements of Art 84 a claim itself needs to define the measurement methods. For the present board, they can alternatively be specified in the description.
This statement is in clear contradiction with T 849/11 and the Guidelines F-IV, 4.11. This point of view is also found in T 2220/12, Reasons 10, T 1731/13, Reasons 1.4. That Guidelines are not binding for boards is one thing, but deviations from an earlier decision of any board or from the Guidelines for Examination is dealt with in Art 20 RPBA20/21; this Art has been superbly ignored by the present board.
Measuring the Vickers hardness, cf. §  of D4, belongs to the common general knowledge of the skilled person and hence does, in principle, not need to be specified in the claim.
The situation is different when it comes to the size of the spangles, cf. §  of D4, It is difficult to say that the corresponding parameter belongs to the common general knowledge of the skilled person. Its inclusion in the claim would thus have been mandatory.
Having a method of measurement defined in a piece of prior art under Art 54(3) is rather surprising, not to say daring. A claim should in principle be self-contained. It is not possible to say that it has ever been envisaged in G 1/03 or G 1/16, that a measurement method can be merely defined in a piece of prior art, and the more so if this piece of prior art is prior art under Art 54(3).
Contradiction with existing case law – reference to another document
Features from a cross-referenced document are only allowed under the following conditions:
The description as originally filed leaves the skilled reader without doubts as to the fact that
i) protection is or may be sought for those features
ii) such features contribute to solving the technical problem underlying the invention
iii) such features are precisely defined and identifiable within the disclosure of the reference document
That Guidelines are not binding for boards is one thing, but deviations from an earlier decision of any board or from the Guidelines for Examination is dealt with in Art 20 RPBA20/21; this Art has, here as well, been superbly ignored by the present board.
Disclaimer and Art 123(2)
In spite of what the board might have said under Art 123(2), the introduction in the claim as maintained, be it in the disclaimer, of the Vickers hardness and the size of the spangles, leads to a problem under Art 123(2), as both those parameters were not disclosed in the application as filed.
Objections under Art 83/123(2)
Once the board had admitted that the provisions of Art 84 were fulfilled, it followed for the board that those of Art 83 were as well fulfilled.
However, as the Vickers hardness and the size of the spangles were not disclosed in the original application, it is doubtful that Art 123(2) was fulfilled.
If the conditions of Art 83 are not fulfilled, this objection can only be overcome by infringing Art 123(2). the mere reference in paragraph  of the amended description that “Patent literature PTL 7 is disclaimed”, does by no means provide “transparency concerning the parameters referred to in the disclaimer of claim 1″.
For the board, “it is clear for the skilled person that the parameters referred to in the disclaimer are measured by the methods indicated in D4, paragraphs  and ”.
However, there is no trace in the amended patent of a reference to paragraphs  and  of D4. This should have been a bare minimum.
On the procedure
The proprietor of EP 2 980 260 is JFE Steel Corporation Tokyo 100-0011 (JP).
EP 2 980 260 bears the following classifications C23C 2/12, C23C 2/06, C23C 2/02, C23C 2/26 and C22C 1/10.
The proprietor of D4=EP 2 957 648, prior art under Art 54(3) is JFE Steel Corporation Tokyo, 100-0011 (JP).
EP 2 957 648 bears the following classifications C23C 2/06, C23C 2/12, C23C 2/28, C23C 2/40, C23C 2/02, C22C 18/04 and C22C 21/10.
It is thus somehow surprising that in spite of the numerous corresponding classification units (see the italics), it was the opponent which found out a prior art under Art 54(3) belonging to the proprietor of the patent at stake.
It is alas not the first time that a board ignores Art 20 (or 21) RPBA20/21. Furthermore, if a method is not properly defined in the original disclosure (or in the disclosure of a prior art document), it cannot come as a surprise that an opponent cannot present verifiable facts when it comes to a lack of sufficiency. In such situations, this kind of argument from a board is not really convincing. Actually, the same is also valid for T 1011/21 recently commented on this blog.