T 0416/88 31-05-1990

Reasons for the Decision

1. The appeal is admissible.

2. The first issue to be decided in respect of the Respondent's main request is whether the patent discloses the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art (Article 100(b) EPC).

This issue was raised for the first time in the Appellant's Statement of Grounds of Appeal but nevertheless considered by the Board.

It was raised specifically in view of the condition "if said track position indicated by said positioning information is defective", mentioned in the penultimate feature of Claim 1, i.e. in effect in view of the fourth characterising feature "determining whether or not a track position indicated by said positioning information is defective".

On the contrary, the Respondent submits that the implementation of this feature is no problem for the skilled person.

The Board agrees with this latter view. Determining whether or not a track position is defective is on the basis of establishing a list of defective tracks and therefore to be regarded as a prerequisite for any method using a defective/substitute track table memory such as, for instance, according to D1 or D2 to D8 (assuming that what is proposed in D3 and described in D4 to D8 has been used prior to the claimed invention as suggested by D2 and Mr Henke's "Eidesstattliche Erklärung") or D10. Considering that, therefore, such determination of defective tracks must necessarily be part of the common knowledge, it cannot pose any particular problem to apply the same feature in the context of the fourth characterising feature in Claim 1 with the appropriate consequences for the penultimate (and the last) feature in that claim.

3. As to the second issue, it is to be decided whether the subject-matter of Claim 1 is patentable within the terms of Articles 52 to 57 (Article 100(a) EPC), more particularly whether it is novel (Article 54) and involves an inventive step (Article 56).

4. As a prerequisite, however, for a decision on this point it must be sufficiently clear what the subject-matter of Claim 1 is.

Lack of clarity of Claim 1 has been contended, by the Appellant, particularly in view of the last feature in Claim 1 "transferring said positioning information to said selected disc unit as a positioning instruction".

This feature is indeed unclear because the fourth characterising feature "determining whether or not a track position ... is defective" presupposes that a positioning to a particular track position has already taken place and this is confirmed by Figure 3 (step a) and its description (column 4, lines 5 to 8), so that another positioning instruction would not seem to be required.

However, lack of clarity is not one of the admissible grounds for opposition (Article 100 EPC) and would not, therefore, be an admissible objection against a granted, unamended claim. It is only allowed, and indeed required in such a case, to interpret the unclear feature of the unamended granted claim using the description and drawings (Article 69 EPC).

If this is done in the present case, it is immediately clear that the last feature is intended to refer to an instruction for the carrying out of step i (Figure 3), i.e. it is to be interpreted as meaning that, if the result of the fourth characterising feature (step d) is "NO", an instruction is transferred to the selected disc unit for the carrying out of a read or write operation (R/W) to the data field following the address field (column 4, lines 34 to 35).

As an aside, it should be mentioned that, similarly, the third characterising feature in Claim 1 is not to be understood as referring to a purposeless "positioning instruction" but, in consistency with the purpose of "controlling magnetic disc units ... for transferring information ..." (cf. preamble), as including an instruction to carry out step i after the head has been positioned to the substitute track (step f), i.e. a read or write operation to the data field following the address field (column 4, lines 28 to 29).

The unamended Claim 1 interpreted in this way, there is no clarity problem left with the subject-matter of this claim.

As to its category, Claim 1 concerns a method of controlling magnetic disc units in (i.e. which are part of) a computer system which is characterised by typical method steps.

In an invention concerning a method it is not unusual that various method steps are performed on physical (or chemical) items.

Therefore, it is quite normal that a patent claim reciting a method mentions such physical or chemical items.

In present Claim 1 those items consist of what the Appellant has called "apparatus features" When a method claim, as in the present case Claim 1, is formulated in the two-part form, it is only natural that some of the method features, as well as some of the apparatus features, will recur in the prior art part of that claim.

Contrary to the Appellant's contention such an occurrence need not necessarily lead to any doubt concerning the real category of such a claim. Present Claim 1 concerns a method of controlling magnetic disc units in a computer system by summing up pure method steps which are made to influence physical entities. Such a method may be carried out automatically, without human interference. The very character of the features of Claim 1 establish an environment in which any other way of carrying out the claimed method than automatically is hardly conceivable.

Because of this, Claim 1 is construed to be a claim which defines the operation of the system by which the claimed method is carried out automatically without human interference.

This means that Claim 1 is considered to cover only the operation of the system which carries out the method (but not that system proper as an apparatus).

Therefore, the Board is satisfied that Claim 1 is a method claim.

5. As to novelty, the Appellant has never expressly contended that the claimed method, as a whole, has been made available to the public either by means of a written description (e.g. D1, D9, D10) or by use (D2 etc.), and the Board sees no reason to go further into this matter.

The subject-matter of Claim 1 is, therefore, to be regarded as novel.

6. What the Appellant has indeed contended is that some of the characterising features are not novel but known in the same context as those in the preamble of Claim 1.

There are doubts whether this is true (cf. 7.1). But even if it is true (cf. 7.2), such partial non-novelty, or incorrect delimitation (Rule 29(1)(a) and (b) EPC), is also (cf. paragraph 4) not an admissible ground for opposition and would not, therefore, be an admissible objection against the unamended Claim 1 as granted.

7. Thus, the remaining issue to be decided in respect of Claim 1 of the Respondent's main request is whether its subject-matter involves an inventive step.

In the opinion of the Board, this is indeed the case and this conclusion is, in essence, based on the following considerations:

7.1. As to the prior art to be considered, the following is noted:

- D1 discloses a method similar to that defined in the preamble of Claim 1 but does not refer to a plurality of disc units.

- D2 seems to prove that Nixdorf Systems 8870 and 8864 were in fact on the market on the priority date of the present invention and D3 in connection with Mr Henke's "Eidesstattliche Erklärung" as well as D4 to D8 would seem to show that in those systems also a method similar to that defined in the preamble of Claim 1 was implemented.

- D9 discloses also a method similar to that defined in the preamble of Claim 1 but does not further specify the defect skip as involving storing addresses of substitute track positions.

- D10 discloses also a method similar to that defined in the preamble of Claim 1 but again does not refer to a plurality of disc units.

On the assumption made before (paragraph 2) in respect of D2 to D8, the Board therefore accepts that all of these four pieces of prior art (D1, D2 to D8, D9, D10) are relevant enough to be considered and does not, in particular, disregard D10 as late filed (Article 114).

7.2. The Board further accepts that some of the characterising features of Claim 1 are not novel insofar as they are implicit in one or the other of the aforementioned pieces of prior art, although this does not necessarily mean that they are known in exactly the context defined in the preamble of Claim 1.

More particularly, it would seem that in any method using a defective/substitute track table memory (such as in D1 or D2 to D8 or D10) not only the first characterising feature of Claim 1 is implemented, but also the second and third, inclusive of its proper interpretation (cf. paragraph 4), can be regarded as necessarily present.

7.3. This does not, however, hold for the fourth characterising feature and, consequently, for the fifth (penultimate) characterising feature in Claim 1 and for the last feature in its proper interpretation (paragraph 4).

D1 does not disclose any such feature. Nor does D9.

From D3 it could be derived that in the system mentioned in D2 the substitute track table is set up only during formatting and not updated during normal operation. That would seem to follow also from D4 (page 7-17) and from D5, D6, D7, and D8.

The only prior art document which would indeed seem to go beyond such a "static" substitute track storage is D10.

This document discloses to modify the content of the alternate track table memory (page 627). As a matter of course, such a modification is only required if and when more tracks have become defective and this implies further that somehow it must be determined whether or not a track position has become defective during use. Up to this point, the fourth and fifth characterising features in Claim 1 will have to be regarded as known per se from D10.

7.4. At this point, it must, however, be considered that D10 is concerned with an implementation of a logical to physical track address translation table by an alterable read only memory (ROM) (page 625). In this context, the "field tool" which must be "available" for the modification of the table content (page 627) can only be understood as being a real tool other than software. The Respondent's submission that, for instance, it can be an ultraviolet light source, appears not unreasonable.

This would moreover mean that indeed, as submitted by the Respondent, the alterable ROM must be taken out of the disc unit controller for allowing its content to be modified.

As a further consequence of this, no updating during operation of the computer system is possible.

7.5. Until here it would seem that the parties' views do not differ widely from each other.

Where the parties disagree is whether or not D10 would render it obvious to a person skilled in the art to update the content of the substitute track table memory dynamically at every time a track not recorded in the memory is accessed, by determining at this instant whether it is defective or not, and, if it is, by storing it in the table, provided that the memory is of a kind which allows that, such as a RAM.

The Appellant submits that this is the case but the Respondent disputes this.

In the opinion of the Board, the Appellant's submission is unconvincing because it would require that some hint is given in D10 or any other prior art document that updating during operation would be desirable, but no such hint can be found.

It may - on the contrary - even be that the skilled person was deterred from considering determining whether a track is defective during operation of the computer system by the fact that such a step is time-consuming and thus against the trend to make computers as fast as possible. The Respondent has agreed that the claimed method is less rapid than one which relies on an unalterable substitute track table.

For these reasons, dynamically updating the content of this table (cf. also the description, column 2, lines 43 to 45) is to be regarded as a novel problem and its solution according to Claim 1 as unobvious.

8. It follows from the above (in particular paragraphs 2, 5 and 7) that none of the grounds for opposition mentioned in Article 100, particularly (a) and (b), EPC would prejudice the maintenance of the patent with Claim 1 unamended.

Claims 2 to 4 being dependent claims, it follows further, as a matter of course, that their subject-matter is also patentable (Article 100(a) EPC). Furthermore, sufficiency (Article 100(b) EPC) is not at issue for these claims, so that the maintenance of the patent with these claims unamended would also not be prejudiced by any of the grounds for opposition.

In such a situation, Article 102(2) EPC requires that the opposition is rejected and this means in the present case, that the appeal is to be dismissed in accordance with the Respondent's main request.

No room is, therefore, left for considering whether Claims 2 to 4 meet the formal requirements of the Convention such as Article 84 EPC.

An objection which was, in effect, a lack of clarity objection, was made by the Board, in its Communication of 9 February 1990, against Claims 3 and 4 only in view of the Respondent's request at that time that the patent be maintained as amended, i.e. in accordance with Article 102(3) EPC which would require that the patent meets the (all) requirements of the Convention. But this objection has been overturned by the Respondent's new main request that the opposition be rejected by dismissal of the appeal, i.e. the patent be maintained unamended according to Article 102(2) EPC for which a possible lack of clarity objection is not relevant.

9. No particular reference is further, in this situation, required for the Respondent's auxiliary requests.

It suffices to state that the amendments incorporated in those auxiliary requests have proven to be, in effect, unnecessary because they are only intended to make explicit what is already implicit in the unamended claims and what can be derived from them by interpretation using the description and drawings.

10. In effect, the Opposition Division's decision to reject the opposition must therefore be confirmed.