T 0552/06 18-08-2010

1. Admissibility of the appeal

The appeal is admissible.

2. The absence of the appellant at the oral proceedings

2.1 As announced in advance, the duly summoned appellant did not attend the oral proceedings. According to Rule 71(2) EPC 1973, the proceedings could however continue without him. In accordance with Article 15(3) RPBA (Rules of Procedure of the Boards of Appeal of the European Patent Office, OJ EPO 2007, 536), the board relied for its decision only on the appellant's written submissions. The board was in a position to decide at the conclusion of the oral proceedings, since the case was ready for decision (Article 15(5) and (6) RPBA), and the voluntary absence of the appellant was not a reason for delaying a decision (Article 15(3) RPBA).

2.2 Also the fact that in its reply to the summons the appellant had indicated his readiness to discuss with the board, either on the date of the oral proceedings, or in advance thereof, "any outstanding matters which might lead to a further requirement to amend the application" was not a reason for the board to delay its decision. According to established case law, the EPC foresees the absolute right to oral proceedings under Article 116(1) EPC 1973, but not the right to an informal interview or an informal telephone consultation (cf. Case Law of the Boards of Appeal of the EPO, 6th edition, 2010, VII.B.2.7.2). Hence the board was not required to contact the appellant by holding a telephone interview, for instance with the rapporteur, either after receipt of the response dated 24 June 2010 or on the day of the oral proceedings. Also a further communication by the board after the summons to oral proceedings was not necessary. Under Rule 100(2) EPC the board shall invite the parties "as often as necessary" to file observations. In the present case oral proceedings were arranged as requested by the appellant. The purpose of oral proceedings is to give the party the opportunity to present its case and to be heard. However a party gives up that opportunity if it does not attend the oral proceedings. It is also the board's view that by filing amended claims before the oral proceedings and then not attending those oral proceedings the appellant must also expect a decision based on objections which may be raised against such claims in his absence, Article 15(3), (6) RPBA. In the present case the board had already raised objections concerning the clarity of the claims then on file in the annex to the summons to oral proceedings. Since this objection still applied to the claims of the appellant's sole request, filed with the reply to the summons, the board considered a further communication to be unnecessary. Finally, the board notes that the appellant did not request that the oral proceedings be cancelled and the procedure be continued in writing.

3. Admissibility of the appellant's sole request

3.1 The request concerns an amendment of the appellant's case after oral proceedings have been arranged. Under Article 13(1) RPBA any amendment to the appellant's case after he has filed his grounds of appeal may be admitted and considered at the board's discretion. The discretion shall be exercised in view of inter alia the complexity of the new subject-matter submitted, the current state of the proceedings and the need for procedural economy. Moreover, according to Article 13(3) RPBA, amendments sought to be made after oral proceedings have been arranged shall not be admitted if they raise issues which the board cannot reasonably be expected to deal with without adjournment of the oral proceedings.

3.2 In the present case the board finds that the amendments made to the claims and description are in response to the objections raised in the annex to the summons to oral proceedings and do not require adjournment of the oral proceedings. The appellant's sole request is consequently admitted into the proceedings, Article 13 RPBA.

4. The requirements of Article 123(2) EPC

The board finds no reason to object to the amendments made to the application and concludes that the amendments satisfy Article 123(2) EPC.

5. The invention

The invention, as now claimed, relates to preventing unauthorized copies of analogue video signals being made by standard (also termed "non-compliant") video recorders; see page 4, lines 18 to 23, and page 5, lines 4 to 15, of the description. In essence, this is achieved by scrambling or encrypting the video signal and then inserting data constituting a key into a predetermined part of the video signal which cannot be recorded by a standard (or non-compliant) video recorder and is thus "hidden" from it. In contrast, "compliant" video recorders can extract and use the hidden data to unscramble or decrypt the video signal; see page 5, lines 7 to 10, of the description.

6. Clarity, Article 84 EPC 1973

6.1 In the annex to the summons to oral proceedings (see point IV above) the board objected inter alia that all four independent claims were unclear, since the features of inserting encoded data into a predetermined part of a modified video signal, set out in each of the independent claims, were merely defined implicitly by the fact that the predetermined part of the modified video signal was arranged to only be recorded with the modified video signal by "compliant" digital video recorders, there being no explicit definition of the features of such "compliant" digital video recorders. The claims did not make clear the essential features of the predetermined part of the modified signal to achieve the desired effect of hiding the data from non-compliant video recorders. Hence although, in the case of a known video recorder, i.e. a "problematic standard (non-compliant) video recorder" (see page 4, lines 4 to 15, of the description), it might be deduced by implication what the term "compliant" was intended to mean, and how a video signal could be modified to hide the encoded data from this particular standard (non-compliant) video recorder, the scope of the subject-matter for which protection was sought was unclear, at least at the borderlines.

6.2 All four independent claims have now been amended to set out essentially that data which is a key for descrambling or decrypting an analogue video signal is inserted in a predetermined part of the video signal so that it is hidden from "standard" analogue video recorders such that it will not be recorded thereby. The predetermined part of the video signal can be modified in one of three ways set out in the claims to achieve this effect. The claims do not set out which way to chose for a given type of standard recorder. Therefore each of the three different solutions (which were previously defined in different dependent claims) should contain the essential features setting out how to modify the predetermined part of the video signal in order to hide the data from standard analogue video recorders (of which there are many types; see, for example, page 5, line 17, to page 6, line 22, of the description). The values of the "selected voltage level", the "predetermined frequency" and the "blanking level" cited in the claims completely depend on the inherent characteristics of known (and future) non-compliant video recorders. The description does not give clear guidance as to how to select these values in general for standard video recorders, let alone for standard analogue video recorders. Therefore the board finds that the clarity objection raised in the annex to the summons to oral proceedings concerning the claims then on file still applies to the claims of the appellant's sole request. As the appellant has already had the opportunity to comment on this objection in the response dated 24 June 2010 and the appellant could have expected this objection to be raised against the present claims, the board finds that the requirements of Article 113(1) EPC 1973, regarding the appellant's opportunity to present comments, are satisfied even though the appellant did not make use of his opportunity to present comments at the oral proceedings.

6.3 The lack of clarity of the claims, understood in the context of the description and figures, can be illustrated by taking the embodiment disclosed in the context of figures 2 to 4; see also page 6, line 8, to page 9, line 4, of the description. According to this embodiment, encoded data is inserted in the vertical blanking interval (VBI) of an analogue video signal in an amplitude range, namely that below -48 mV (see page 7, lines 22 to 24), which is lost (clipped) "when converted to a CCIR-601 type signal's digital representation" during digitization in a digital video recorder. In the light of this embodiment the skilled person would understand that the encoded data has to be inserted in the video signal during the VBI and below -48 mV (or, more generally, the digitization limit level) in order to hide it from a digital video recorder. However claims 1 to 4 set out hiding encoded data in a predetermined part of the video signal from standard analogue video recorders. The description and figures do not disclose generally applicable voltage levels in the case of standard analogue video recorders. It is consequently unclear, when interpreting the claims in the light of the description and figures, what "selected voltage level" or "blanking level", set out in the claims, is required to achieve the claimed effect of hiding the encoded data from standard analogue video recorders.

6.4 Claims 1 to 4 are consequently unclear, contrary to the requirements of Article 84 EPC 1973.

6.5 The appellant's argument that the applicant is entitled to a broad functional protection because of the various possible ways of achieving the desired result is not convincing in the present case, where the description and figures do not disclose sufficient details of how the desired result is achieved for the meaning of the terms set out in the claims to be clearly understood.

6.6 The board notes that the reasons for the decision under appeal set out a similar objection, albeit against differently worded claims (see point II above).

6.7 The board could not see a simple amendment which might have overcome this objection.

7. Conclusion

Since the appellant's sole request cannot be allowed, the appealed decision cannot be set aside.