T 0911/10 (Source code protection/MSTAR) 17-01-2014

Reasons for the Decision

1. According to Article 15(3) of the Rules of Procedure of the Boards of Appeal (RPBA) the board is not obliged to delay any step in the proceedings, including its deci­sion, by reason only of the absence at the oral pro­cee­dings of any party duly summoned who may then be trea­ted as relying only on its written case. In the present case, the board was in a position to take a decision at the end of the hearing. With the summons the board had been informed the appellant that amendments would be exa­mined as to their admissibility and their compliance with the EPC even in the appellant's absence. The board also notes that the decision under appeal contained, if only in a section entitled "Auxiliary observations", a number of objections (under Articles 83, 84 EPC 1973 and 123 (2) EPC) against the claims corresponding to the now pending claims. The appellant should therefore have been aware that the amended claims even if admissible might be deficient in other ways.

2. In its letter of 20 December 2013 the appellant's representative asked to be contacted by a member of the technical board of appeal to permit minor deficiencies to be remedied. No legal provision governing the appeal proceedings foresees such a possibility. The rapporteur acts on behalf of the board when addressing the party (Article 5(3) RPBA). Apart from the fact that a tele­phone conversation does not conform to the principle of collec­­tive decision making, it may be a source of new issues or commit the­ board without preliminary dis­cussion (see T 263/07, reasons 2). By contrast, the oral proceedings offer the appellant sufficient oppor­tunity to remedy any outstan­ding deficiencies. If the appellant chooses not to be present, it cannot expect the board to take a reques­ted alternative course of action not provided for by the rules of procedure. The board therefore refuses the appellant's request for a telephone conversation.

3. The main and auxiliary requests subject to the appeal were filed on 13 November 2013 after the board's commu­nication. According to Rule 13(1) RPBA they constitute an amendment to the party's case which the board has discretion not to admit in view of inter alia the current state of the proceedings and the need for pro­ce­­dural economy. In this regard it is an established criterion in the jurisprudence of the boards of appeal to assess whether late filed claims are clearly allow­able. In the following, the board will assess the new claims accordingly.

4. The application generally relates to the protection of a plain text file, especially containing com­pu­ter pro­gram source code, against illegal copying and sharing once it has been distributed to an authorised user (see original description, p. 1, 4th par.). The central idea of the in­vention is to distribute the file in encrypted form - as a "protected file" - along with a "user li­cence" and a "user program", especially an editor. The user program determines with the license whether "it is en­ti­tled to run" and, if it is, decrypts the file, also aided by the li­cense, and offers it to the user to edit (p. 4, 3rd par. - p. 5, 1st par.; figs. 1 and 2). The edited file is stored in terms of the diffe­rences com­pared with the original file. These diffe­rences are also stored in en­­cryp­ted form (par. brid­ging pp. 4-5; p. 5, 2nd par.). Furthermore, the application foresees that the invention prevents the "image of the original file" - i.e. the original file in decrypted form - from being copied to any file, other than as a further protected file (see e.g. p. 1, penult. par.).

5. In the annex to the summons (points 6.2 and 6.3) the board had expressed the view that the problem addressed by the invention is not achieved if it is merely possible to save the ori­­­ginal and the difference files in encrypted (or obfus­ca­­ted) form but only if such sto­rage is enforced, i.e. if it is made impossible that the ori­ginal file or the changes are stored in plain text form. At a minimum this implied that it is a ne­cessary feature of the "computer tool" that it does not offer the user the function of storing the protected text file unen­cryp­­ted. The board observed that the then pending claims did not contain this limitation which appeared to constitute a lack of essential features and a defi­ciency under Article 84 EPC 1973. The board fur­ther pointed out that the description specified the goal of "preventing the image of the original file from being copied to any file other than as a further pro­tected file" only in broad terms without also disclo­sing how this goal was actually achieved (see p. 1, penult. par.; p. 2, 4th par.) and expressed its doubt as to whether the description provided adequate basis to incorporate the missing feature in a sufficiently clear manner.

6. In response to this objection, the appellant amended the independent claims of both requests by adding the phrase "whilst preventing the image of the original plain text file from being copied to any file, other than as a fur­ther protected file, by storing the image of the original plain text file in memory of a compu­ter, which memory is not backed up to a swap file of the compu­ter" (henceforth "the additional feature").

6.1 For original disclosure, the appellant referred to the description on page 1, last paragraph, which discloses that the "image is preferably protected against copying by arranging that the memory in which it is stored is not backed up to the computer memory swap file so that it cannot be found by programs that might read the image file", and on page 4, penultimate paragraph, which refers to a "human readable image" which "is held in the memory of a computer which is not backed up to the computer swap file so that the image cannot be found by other programs on the computer".

6.2 The additional feature corresponds substantially to the one which had caused the problem under Rule 137 (4) EPC pre-2010 be­cause, according to the decision under appeal, it was neither searched nor unitary with the original set of claims. The appellant addressed this fact by arguing, in its response of 13 November 2013, that even if the additional feature had not been searched, it was unitary with the original claims so that Rule 137 (5) EPC - equivalent to Rule 137 (4) EPC pre-2010 - did not apply.

7. The board notes that the claims do not specify any further detail regarding the memory structure and memory management of the computer system on which the invention is meant to be implemented, nor is such detail disclosed in the original application.

7.1 Firstly, it appears that the claims do not require the computer system to have any swap file at all, as they only require that the image "is not backed up to a swap file of the computer" (emphasis added). In a computer with­out any swap file this feature would be trivially satis­fied without requiring any explicit method step or any modification of the user program.

7.2 Secondly, problems remain even on the assumption that the computer has a swap file. Typically, a compu­ter swap file is a means for the operating system to simu­late extra memory by moving currently unused data from the RAM to a hard disk. The swap file being under the con­­trol of operating system, application pro­grams (such as the claimed editor program) are typically not - and need not be - aware of the fact that swap memory is be­ing used. The claims further specify the existence of some memory which is not backed up, despite the exis­tence of a swap file. Again, it is normally a function of the opera­ting system to allocate memory for an appli­­cat­ion pro­gram to use, and the application program has no control over this choice. The description however does not disclose how the claimed result is achieved that the pertinent memory is not backed up. Arguably, there­fore, the description does not suffi­ciently dis­close the additional feature as required by Article 83 EPC 1973. Moreover, it is doubtful whether the means employed to achieve this result is a feature of the application program, of the operating system or, possi­bly of both. Accordingly it is unclear whether and to what extent the additional feature constitutes a limi­­tation of the independent computer program claims, i.e. of claim 12 of the main and claim 10 of the auxil­iary request, Article 84 EPC 1973.

7.3 Thirdly, it remains questionable whether the intended effect of protecting the original plain text is achieved by the subject matter of the independent claims even though they comprise the additional feature, as long as they do not also specify expressly that the computer program prohibits the user from simply storing a plain text file in unencrypted form, Article 84 EPC 1973.

8. In view of the above the board comes to the conclusion that the independent claims of the amended claims are not clearly allowable at least under Articles 83 and 84 EPC 1973. Thus the board exercises its discretion under Rule 13(1) RPBA and does not admit the new requests into the procedure.

9. There being no admitted request, the appeal as a whole has to be dismissed.