T 2703/18 - Search fee refund

Key points

• This is an appeal against a decision of an Examining Division refusing the application and refusing the refund of an additionally paid search fee under Rule 64.
• "The examining division refused the application on the basis that the main request and auxiliary requests 1 and 2 did not meet the requirement of an inventive step, Article 56 EPC, and because auxiliary request 3 was not admitted under Rule 137(3) EPC. It rejected the request to refund a further search fee because it confirmed the search division's non-unity objection against the original set of claims."
• An amended set of claims was filed in appeal after the Board cited new prior art of own motion and in reply to clarity objections of the Board. The Board considers those claims to be allowable. 
• The invention is interesting but too advanced software technology for me. 
• D1 was the master thesis of one of the inventors on the same topic.
• "The first two authors of D8 are the inventors of the present application. D8 is reference [137] in the later-published PhD thesis of the second author, to which the appellant drew the attention of the board in the grounds of appeal (page 26, fifth complete paragraph)."
• "The board noted that it was not convinced by the examining division's inventive step lines of argument starting from either D1 or D2. However, claim 1 of the main request and auxiliary requests 1 and 2 did not appear to involve an inventive step starting from D2 combined with common general knowledge as illustrated by D8."
• Turning to the requested refund of the additionally paid search fee: "As the appellant's refund request concerned only the further search fee paid for original claims 10 and 11, the examining division had to assess whether the communication under Rule 64(1) EPC was "justified" - within the meaning of Rule 64(2) EPC - to the extent that it required a further search fee to be paid for original claims 10 and 11."
• "In a number of board of appeal decisions, it has been considered that the scope of the review under Rule 64(2) EPC (previously Rule 46(1) EPC 1973) to be carried out by the examining division is limited to the consideration of certain facts and/or arguments."
• " it was considered in T 188/00 that "a review of the finding of lack of unity of invention has to be carried out having regard only to the facts presented by the search division in its communication under Rule 46(1) EPC [1973]" and that "the examining division has to base its review solely on the documents cited in the partial search report and on the specification of the different inventions drawn up by the search division, while taking into account argu­ments which the applicant may have submitted in support of his request for a refund"
• "The limitation to the facts presented by the search division, in particular the cited documents, postulated in T 188/00, has been followed, for instance, in T 1476/09, reasons 3, T 2285/17, reasons 4.2, and T 2873/19, reasons 9.1. In T 188/00 and in T 1476/09, the board found that the examining division's reasoning why the communication under Rule 64(1) EPC had been justified was incorrect because it relied on prior art that had not been cited in the partial search report (see T 188/00, reasons 4.6, and T 1476/09, reasons 3)."
• "The present board agrees with T 188/00 to the extent that the examining division may only find that the communication pursuant to Rule 64(1) EPC was justified within the meaning of Rule 64(2) EPC on the basis of the facts regarding the prior art presented by the search division with that communication, in particular the documents cited in the partial search report including sheet B.

  On the other hand, the present board considers that a finding that the communication was not justified may well be based on further facts (for instance in the circumstances of the case in T 755/14)."

• "the present board considers that, in the context of Rule 64(2) EPC, the examining division may, in order to find the communication under Rule 64(1) EPC to have been justified, complete a reasoning outlined by the search division with the communication but may not replace it by an entirely different reasoning, even if based on the same prior art."

• "This position takes account of the fact that the applicant has to decide whether or not to pay further search fees only on the basis of the information provided with the communication under Rule 64(1) EPC. Where the search division decides to provide arguments with the communication as to why a further search fee would have to be paid, this is to enable the applicant to understand at this stage why the invitation is justified. The applicant would inevitably rely on these arguments to assess whether it is actually entitled to a complete search for a single search fee and, if so, would pay the further search fee with the expectation that it will be refunded upon review. In the board's view, it would be undesirable as a matter of fairness that such a refund may later be refused by the examining division because the communication is considered to have been "justified" based on an entirely different reasoning than that contained in the communication."

• "When assessing whether the application documents on file comply with the requirement of Article 82 EPC, as a requirement for the grant of a patent, the examining division is not bound by the search division's opinion on unity of invention "

• "for the reasons given at points 16.3 and 18.1 above, the board is not convinced by the reasons given by the examining division on why claim 1 of the then main request lacked an inventive step over D1 or D2 combined with D7. It follows that the board is also not convinced by the reasons given by the examining division in the context of Rule 64(2) EPC (and a fortiori by the search division) on why original claim 1 lacked an inventive step."

• "The additional search fee was paid for claim 10. ": The reasoning of the examining division, like that of the search division, ignores at this stage the depen­den­cies of these claims [i.e. claim 10] (apart from their dependency on claim 1) and appears to have only considered the additional features defined in each of the claims."

• "Original claim 10 was directed to a "method according to one of the preceding claims 3 to 9" and original claim 11 to a "method according to one of the preceding claims 3 to 10". Hence, at least the subject-matter of original claim 3 (itself being dependent on original claim 1) was common to the first and the second "search subjects".  They may only be non-unitary if original claim 3 was not inventive, but this has neither been alleged nor established by the examining division in its reasoning on Rule 64(2) EPC.

• " The board therefore concludes that the communication pursuant to Rule 64(1) EPC was not justified and the further search fee paid for original claims 10 and 11 is thus to be refunded, Rule 64(2) EPC."

• The decision also contains interesting remarks on Art.82. 

EPO 

You can find the link to the decision and an extract of it after the jump.

https://www.epo.org/en/boards-of-appeal/decisions/t182703eu1

Refund of further search fee

20. In a communication pursuant to Rule 64(1) EPC issued on 12 August 2014, including a partial European search report, the search division indicated that the original set of claims did not comply with the requirement of unity of invention, Article 82 EPC, identified three "search subjects":

(1) original claims 1-9, 12, 13, 15-17,

(2) original claims 10, 11,

(3) original claim 14,

and invited the applicant to pay two further search fees if the European search report was also to cover the "search subjects" (2) and (3) (Form 1507U in conjunction with the annex "sheet B" of the partial European search report).

21. In sheet B, the search division provided the following reasoning.

21.1 In sheet B, point 1, the search division stated that "a method for authenticating objects comprising the steps of claim 1 is known from D1 or D2", followed by an indication of passages of D1 and D2 for some features of claim 1. It was said that "in D1 the object instance must be recognized and its pose estimated before authentication [...] and it is trivial to postulate that this task should be carried out automatically", and that this applied also to D2. The search division then indicated that "a method for object recognition and pose estimation notorious in the art of machine vision to be used for this purpose is the bag of features method", and stated that it comprised "recog­ni­tion codebook training and its organization as a tf-idf file, object enrollment, object verification by comparing the features extracted from the current image with the codebook". For the "bag of features" method, reference was made to "online textbook: Szeliski - Computer Vision: Algorithms and Applications: Instance recognition p.690" but no corresponding document was cited in the partial search report. The search division concluded that "consequently, the subject-matter of claims 1-5 does not involve an inventive step (Article 56 EPC) with respect to D1 or D2".

21.2 In sheet B, point 2, the search division further indi­ca­ted that "with respect to the prior art, dependent claims 2-17 refer to potential special technical fea­tures which are grouped as follows: [...]", with an indication of features and - in all cases but the first one - solved problems for original claims (2-5), (6), (7, 8), (9, 12, 13), (10), (11), (14), (15-17). The following was indicated for original claims (2-5), (6), (10) and (11) (which are the only relevant ones for this decision):

"Claims 2-5 referring to various commonly known features of object recognition / authentication using a dictionary of features (BoF)";

"Claim 6 referring to the features of the choice of descriptors and/or geometrical relations between the keypoints solving the known problem of ensuring geometric consistency of multiple matched keypoints";

"Claim 10 referring to the feature of soft assignment in the quantisation step of codebook / feature dictionary generation by the function Rin(k) =Q(((xk )T (cn - c') - din /2)/sigma)";

"Claim 11 referring to the features of patch-wise alignment using local projection transforms solving the known problem of aligning the current object with a template object".

21.3 In sheet B, point 3, the search division concluded that because "the features of claim 1 are obvious", the aforementioned "groups of features" "solve different, juxtaposed problems" and there were "no common or corres­ponding technical features or effects in the two groups of claims" (meant was presumably: any two of these groups of claims), there was no single general inventive concept "relating the above groups". The application therefore lacked unity of invention, Article 82 EPC.

21.4 In sheet B, point 4, the search division indicated that original claims 2-9, 12, 13 and 15-17 were "grouped into one search subject", original claims 10 and 11 into another search subject, and original claim 14 appa­rently into a third one (and objections under Article 83 or 84 EPC were suggested in respect of that claim).

22. The appellant paid a further search fee only for original claims 10 and 11, i.e. the second "search subject".

23. The (final) European search report was issued on 31 October 2014, covering original claims 1-13 and 15-17. In the accompanying European search opinion (section I), the search division repeated the reasons given in sheet B of the partial European search report.

24. When entering the examination phase, the appellant requested a refund of the further search fee paid for original claims 10 and 11 (letter of 21 March 2016). The reason was that original claim 1 was inventive and its characterising part, which had not been considered in the search division's reasoning, represented the single general inventive concept shared by original claims 1 to 17. Moreover, it appeared that "questions of inventive step and unity of invention [had] been intermingled".

25. In the contested decision (point 7), the examining division confirmed the search division's finding of non-unity of the original set of claims and rejected the refund request.

25.1 The examining division maintained the search division's finding of lack of inventive step of original claim 1 simply by reference to the reasons it gave in the decision for claim 1 of the then main request, which was said to consist of "the subject-matter of original claim 1 further specified with features of original claim 3" (decision, point 7.1).

25.2 The remainder of the examining division's reasoning (decision, points 7.2 and 7.3) is practically verbatim that of the search division in sheet B, points 2-4 (see points 21.2 to 21.4 above), with the added remark that "the applicant's argument rests entirely on the allowability of claim 1" and that "the Examining Division does not share the view that original claim 1 is allowable and thus maintains the original objection of lack of unity under Article 82 EPC".

26. In the grounds of appeal (point IX.1), the appellant argued that "all [...] embodiments and options are related to the subject matter of claim 1 in unitary manner, given that the method of claim 1 uses both identification - and authentication features which might be in the form of claims 5 to 10, respectively of claims 11 to 14"; this applied to claim 1 according to the then main request and all auxiliary requests. The appellant also argued that "it isn't clear why and how the examining division combined claims 10 and 11 into a group and considered them as forming a (second) group of unitary inventions".

27. Rule 64(1) EPC provides that if a European patent application lacks unity, the applicant shall be informed that, for the European search report to cover any invention other than that first mentioned in the claims, a further search fee has to be paid.

Rule 64(2) EPC provides that any fee paid under Rule 64(1) EPC shall be refunded if, during the examination of the European patent application, the applicant requests a refund and the examining division finds that the communication under Rule 64(1) EPC was not justified.

28. As the appellant's refund request concerned only the further search fee paid for original claims 10 and 11, the examining division had to assess whether the communication under Rule 64(1) EPC was "justified" - within the meaning of Rule 64(2) EPC - to the extent that it required a further search fee to be paid for original claims 10 and 11.

29. The board considers it appropriate to first determine the scope of the review under Rule 64(2) EPC by the examining division (and by the board) before reviewing the reasoning provided by the examining division in the decision.

30. The scope of the review under Rule 64(2) EPC

30.1 In a number of board of appeal decisions, it has been considered that the scope of the review under Rule 64(2) EPC (previously Rule 46(1) EPC 1973) to be carried out by the examining division is limited to the consideration of certain facts and/or arguments.

30.1.1 Most notably, it was considered in T 188/00 that "a review of the finding of lack of unity of invention has to be carried out having regard only to the facts presented by the search division in its communication under Rule 46(1) EPC [1973]" and that "the examining division has to base its review solely on the documents cited in the partial search report and on the specification of the different inventions drawn up by the search division, while taking into account argu­ments which the applicant may have submitted in support of his request for a refund" (T 188/00, reasons 4.5).

30.1.2 That the review is limited to the specification of the different inventions drawn up by the search division is generally accepted in the case law and also by the present board, because any invitation to pay a further search fee under Rule 64(1) EPC must be for a specific invention or group of inventions that is to be covered by the search report and can thus only be justified for that particular invention or group of inventions.

30.1.3 The limitation to the facts presented by the search division, in particular the cited documents, postulated in T 188/00, has been followed, for instance, in T 1476/09, reasons 3, T 2285/17, reasons 4.2, and T 2873/19, reasons 9.1. In T 188/00 and in T 1476/09, the board found that the examining division's reasoning why the communication under Rule 64(1) EPC had been justified was incorrect because it relied on prior art that had not been cited in the partial search report (see T 188/00, reasons 4.6, and T 1476/09, reasons 3). In the cases underlying T 2285/17 and T 2873/19, the examining division's reasoning was limited to prior art cited in the partial search report and there was consequently no objection by the board in that respect.

30.1.4 In T 755/14, the board formulated a slightly different criterion. It considered that the review under Rule 64(2) EPC of a non-unity objection raised in the communication under Rule 64(1) EPC must be limited to the determination of whether that objection was justified at the time the communication was issued, and thus whether it was justified under consideration of the prior art that was available at that time (T 755/14, reasons 4). In that case, the board found that the communication under Rule 64(1) EPC had not been justified in view of documents not cited in the partial search report but only cited in the original application (T 755/14, reasons 5, 6.2 and 6.3).

30.1.5 Other decisions have gone beyond T 188/00 by stating that the review under Rule 64(2) EPC is to be based on the facts and arguments presented in the communication under Rule 64(1) EPC: see T 2526/17, reasons 4.7, and T 1414/18, reasons 4.3.

30.2 The present board agrees with T 188/00 to the extent that the examining division may only find that the communication pursuant to Rule 64(1) EPC was justified within the meaning of Rule 64(2) EPC on the basis of the facts regarding the prior art presented by the search division with that communication, in particular the documents cited in the partial search report including sheet B.

On the other hand, the present board considers that a finding that the communication was not justified may well be based on further facts (for instance in the circumstances of the case in T 755/14).

While the board essentially agrees with the position formulated in T 188/00, it is not fully convinced by the reasons provided for it in that decision, nor by the view expressed in T 2526/17 and T 1414/18 that the scope of the review should also be limited to the arguments presented by the search division, at least if understood as a limitation to only those arguments.

Instead, the present board considers that, in the context of Rule 64(2) EPC, the examining division may, in order to find the communication under Rule 64(1) EPC to have been justified, complete a reasoning outlined by the search division with the communication but may not replace it by an entirely different reasoning, even if based on the same prior art.

30.3 Limitation to facts

As regards the position formulated in T 188/00, the board notes the following.

30.3.1 In T 188/00, reasons 4.5, the board argued that this position followed essentially from the wording of Rule 46 EPC 1973 (now Rule 64 EPC). It also referred to the so-called "protest procedure" according to Rule 40.2(c) PCT before an ISA (and the similar procedure according to Rule 68.3(c) PCT before an IPEA) and noted that the boards of appeal had, in this context, ruled that the review of the justification for an invitation to pay additional fees had to be based exclusively on the reasons given in the invi­ta­tion having regard to the facts and arguments submitted by the applicants (reference was made to W 4/93, reasons 2.1 and 2.2).

The board also notes that essentially no additional reasons have been provided in the subsequent decisions cited above that follow T 188/00.

30.3.2 However, notwithstanding their similarities, Rule 64 EPC and Rule 40 PCT (and, a fortiori, Rule 68 PCT) have some notable differences. First, Rule 40.1(i) PCT expressly requires the invitation to pay additional fees to "specify the reasons for which the international application is not considered as complying with the requirements of unity of invention", which Rule 64(1) EPC does not. Secondly, in cases of a protest by the applicant, Rule 40.2(c) PCT foresees a "review body" that examines a "reasoned statement" filed by the appli­cant, decides whether and to what extent it finds the protest justified and orders corresponding reim­bursements, without entering into a dialogue with the applicant. Under Rule 64(2) EPC, the examining division is competent to decide on a refund request at any time during examination. Thirdly, Rule 40.2(c) PCT provides for a reimbursement of paid additional search fees to the extent that the review body "finds the protest justified", whereas Rule 64(2) EPC provides for a refund if "the examining division finds that the communication under [Rule 64(1) EPC] was not justified".

Furthermore, the relevant PCT Guidelines were binding guidance for the EPO when acting as an ISA and for the boards of appeal when they were deciding on protests against the charging of additional search fees under the PCT (G 1/89, headnote and reasons 6), so that several statements in the PCT Guidelines on how unity of invention is to be assessed and the protest proce­dure to be carried out have been taken over in the case law under the PCT already for that reason (see e.g. G 1/89, headnote, and W 21/03, reasons 4). Neither the PCT International Search and Examination Guidelines nor the Guidelines for Examination in the EPO are binding on the boards of appeal when reviewing decisions of examining divisions (Article 23(3) EPC).

30.3.3 Accordingly, the conclusions drawn in the case law for the review of invitations to pay additional search fees under Rule 40.2(c) PCT (or additional preliminary examination fees under Rule 68.3(c) PCT) do not immediately carry over to Rule 64(2) EPC. This applies, for instance, to the observation of the Enlarged Board of Appeal in G 1/89, reasons 8.2, that the review body under the PCT decides without the applicant having had an opportunity to comment. Under the EPC, Article 113(1) EPC ensures that the applicant's right to be heard is guaranteed even if the examining division goes beyond the reasons given by the search division.

30.3.4 As noted in G 1/91, reasons 4.1, the requirement of unity of invention ­under Article 82 EPC, notwithstanding its substantive nature, is "still merely an administrative regu­lation", serving a number of administrative purposes, an important one being financial. In conjunction with Rule 64 EPC, this requirement enables the patent office to collect an amount of fees dependent on the number of inventions or groups of inventions within the meaning of Article 82 EPC and thus approximately commensurate to the work it has to carry out (see also G 2/92, headnote).

30.3.5 In this context, the communication under Rule 64(1) EPC serves the purpose of allowing the search division to limit its initial search to the invention or group of unitary inventions first mentioned in the claims and to ask for a further search fee if the search is to be extended to cover an invention or a group of inventions that is non-unitary with that which has been searched so far.

An invitation to pay a further search fee may thus only have been "justified" in view of the prior art that was available to and considered relevant by the search division at the time the communication was issued.

The examining division may therefore only find that the communication under Rule 64(1) EPC was justified within the meaning of Rule 64(2) EPC on the basis of the facts regarding the prior art presented by the search division with that communication, in particular the documents cited in the partial search report including sheet B.

30.3.6 On the other hand, the present board considers that the examining division may well rely on further facts in a finding that the communication under Rule 64(1) EPC was not justified, for instance in the circumstances of the case in T 755/14 (see point 30.1.4 above) or, say, if further evidence shows that the only document cited in the partial search report and relied on in an a posteriori non-unity finding does actually not belong to the prior art.

30.3.7 Such further facts need also not have been submitted by the applicant. More generally, the board considers that the examining division may find that the communication under Rule 64(1) EPC is not justified for reasons other than those presented by the applicant. Rule 64(2) EPC does not require the refund request to be reasoned and provides that any fee paid shall be refunded if "the examining division finds that the communication under [Rule 64(1) EPC] was not justified", without further qualification (whereas under the PCT the reimbursement requires the protest to be justified - the protest having to include a "reasoned statement" to the effect that the international application complies with the requirement of unity of invention or that the amount of required additional fees is excessive, Rule 40.2(c) PCT).

30.4 Limitation to arguments

As regards the position expressed in T 2526/17 and T 1414/18 that the scope of the review should not only be limited to the facts but also to the arguments presented by the search division in the communication under Rule 64(1) EPC, the board notes the following.

30.4.1 Rule 64(1) EPC does not expressly require the communication to include a reasoning as to why the search division considers the application to lack unity of invention. Literally, Rule 64(1) EPC only requires the communication to include a specification of the inventions or groups of inventions which have been searched and of those for which further search fees need to be paid if they are to be covered by the search report (as otherwise the applicant would not know for what the further search fees are to be paid).

30.4.2 In the present case, the communication was issued on 12 August 2014. At that time, a partial European search report was not accompanied by a search opinion; only the (final) European search report, issued after the time limit for paying further search fees had expired, was accompanied by a search opinion. The Guidelines for Examination in the EPO, September 2013 edition ("EPO Guidelines 2013"), which were then in force, only required the search division to include "the reasoning behind the lack of unity" in the search opinion accompanying the European search report (EPO Guidelines 2013, B-VII, 1.2, and B-XI, 5). Still, it was common for communications under Rule 64(1) EPC to include some reasoning in sheet B of the partial European search report, as in the present case (see also e.g. the cases underlying J 24/96 or T 389/03), but not all such communications did (as also noted in T 756/14, reasons 4.1).

30.4.3 This is contrast to Rule 40.1(i) PCT which requires the invitation to pay additional search fees to specify the reasons for which the international application is not considered as complying with the requirement of unity of invention. This might provide justification under the PCT for limiting the scope of the review to the reasoning and thus to the facts and arguments provided in the invitation. In the case law on the PCT protest procedure, this has led to the conclusion that an additional search fee is already to be reimbursed if the reasoning presented in the invitation is insufficient, as such a deficiency may not subsequently be remedied (see e.g. W 4/85, headnote and reasons 3, W 11/93, reasons 2.5, 3 and 4, and W 9/07, reasons 2).

30.4.4 In the present board's view, a similarly strict limi­ta­tion of the scope of the review under Rule 64(2) EPC to the arguments provided in the communication cannot be justified where the provision of any arguments was at the discretion of the search division. A complete reasoning for the lack of unity of invention may only be required from the examining division if it finds the communication to be justified (Rule 111(2) EPC).

This position is also coherent with the separation of competences between search and examining division foreseen in the EPC, with the consequence that the same standard of reasoning may not be required from the search and the examining division.

30.4.5 The board considers however reasonable that, in the context of Rule 64(2) EPC, the examining division may complete a reasoning that has only been outlined by the search division with the communication under Rule 64(1) EPC but may not replace it by an entirely different reasoning, even if based on the same prior art, to find that the communication was justified.

30.4.6 This position takes account of the fact that the applicant has to decide whether or not to pay further search fees only on the basis of the information provided with the communication under Rule 64(1) EPC. Where the search division decides to provide arguments with the communication as to why a further search fee would have to be paid, this is to enable the applicant to understand at this stage why the invitation is justified. The applicant would inevitably rely on these arguments to assess whether it is actually entitled to a complete search for a single search fee and, if so, would pay the further search fee with the expectation that it will be refunded upon review. In the board's view, it would be undesirable as a matter of fairness that such a refund may later be refused by the examining division because the communication is considered to have been "justified" based on an entirely different reasoning than that contained in the communication.

The board considers reasonable to interpret Rule 64 EPC in such a manner favourable to the applicant in view of the merely administrative nature of this rule (see T 708/00, reasons 6, for similar considerations).

The board also notes that J 24/96, reasons 3, seems to have relied on a similar position as that formulated at point 30.4.5.

30.4.7 The board emphasises that these considerations regar­ding a qualified limitation to arguments presented by the search division concerns only the decision of the examining division on whether further search fees are to be refunded under Rule 64(2) EPC. When assessing whether the application documents on file comply with the requirement of Article 82 EPC, as a requirement for the grant of a patent, the examining division is not bound by the search division's opinion on unity of invention (T 178/84, headnote 1, T 631/97, reasons 3.6; see also J 3/09, headnote 1).

30.4.8 The board also notes that nowadays the invitation to pay further search fees and the partial European search report are systematically accompanied by a search opinion that includes the reasoning for the non-unity findings (EPO Guidelines, March 2024 edition, F-V, 4.1). This change of practice was introduced as a "new service" of the EPO entering into force on 1 April 2017 with the Notice of the European Patent Office dated 3 March 2017 concerning issuing a provisional opinion accompanying the partial search results, OJ EPO 2017, A20. In this notice, it was indicated that "[a]s with international applications (cf. Rule 40.1 PCT), for European patent applications too applicants will in the future [i.e. as from 1 April 2017] be systematically informed about the reasons for the non-unity findings together with the invitation to pay further search fees".

31. Restraint to be exercised in the context of Rule 64 EPC

31.1 As to the appellant's argument that the search division had "intermingled" the requirements of unity of invention and inventive step, the board notes that the search division and the examining division are allowed to make objections of lack of unity of invention a posteriori, i.e. with respect to the prior art (G 1/89, headnote, and T 87/88, reasons 2). The following should however be considered.

31.2 In view of the administrative nature of Article 82 EPC and Rule 64 EPC, and in line with several board of appeal decisions (see e.g. T 806/18, reasons 5.4), an objection of lack of unity should not be insisted upon on the basis of a narrow, literal or academic approach, in particular during search when the possible lack of unity does not necessitate a further search (as also noted in the EPO Guidelines 2024, F-IV, 2.2, and in the EPO Guidelines 2013, F-V, 8).

Using the words of G 1/89, reasons 8.2 (albeit in the context of the PCT), the present board considers that a search division in a communication under Rule 64(1) EPC (or an examining division when reviewing such a commu­nication pursuant to Rule 64(2) EPC) may raise an objection of lack of unity in clear cases but should exercise restraint in the assessment of novelty and inventive step when carrying out an a posteriori assessment of unity of invention and in borderline cases preferably refrain from considering an applica­tion not to comply with the requirement of unity of invention on such grounds.

31.3 More concretely, in the board's view, the restraint to be exercised by the search division in a communication pursuant to Rule 64(1) EPC (and by the examining division in the context of Rule 64(2) EPC) has at least the following aspects.

31.3.1 While findings of lack of unity a posteriori are in principle allowed, they must be raised with caution especially when they rest on an objection of inventive step, as questions of inventive step often constitute the major issue in substantive examination and may be controversial until the end of the examination and/or appeal proceedings.

31.3.2 The search division should refrain from raising formalistic objections based on a literal interpetation of the claims, because the assessment of unity of invention by the search division in the context of Rule 64 EPC only serves the purpose of determining whether a partial search report is to be issued (see also T 631/97, reasons 3.6), and the search according to Article 92 EPC is to be based on the basis of the claims "with due regard to the description and any drawings". Findings on novelty or inventive step of the search division in its communication under Rule 64(1) EPC should thus be robust, especially against foresee­able amendments and against clarity issues that the claims may have.

32. The examining division's reasoning on Rule 64(2) EPC

32.1 In the present case, the search division provided reasons in sheet B of the partial search report why the original set of claims lacked unity of invention a posteriori in view of D1 or D2, as starting point, combined with the allegedly notorious "bag of features" method. For that method, reference was made in sheet B to "online textbook: Szeliski - Computer Vision: Algorithms and Applications: Instance recognition p.690" but a corresponding document was neither cited in the listing of "documents considered to be relevant" of the partial search report nor sent to the applicant with the partial search report.

32.2 The examining division found that the communication under Rule 64(1) EPC was justified and refused therefore a refund of the further search fee paid for original claims 10 and 11 (decision, point 7).

32.3 The examining division noted that claim 1 of the then main request consisted of "the subject-matter of original claim 1 further specified with features of original claim 3" and simply referred to the reasons given for claim 1 the main request to conclude that original claim 1 was not inventive (decision, point 7.1). In doing so, the examining division relied on D1 or D2 combined with common general knowledge exemplified by D7 for the lack of inventive step of original claim 1.

32.4 The board considers that D7, which was only provided to the applicant with the examining division's communication dated 20 September 2016, corresponds to the bibliographical data indicated by the search division in sheet B, so that the examining division's reasoning was correctly only based on facts presented by the search division with the communication.

32.5 The board notes that the appellant complained in the first-instance proceedings (letter dated 21 March 2016, pages 2-3) that "the features of the characterizing part of claim 1 apparently have not been considered" in the search division's objection of lack of inventive step of original claim 1 when deciding on unity of invention.

The board agrees with the appellant that the reasoning provided by the search division in sheet B for the lack of unity a posteriori does not address all the features of claim 1 and is more an outline of an objection than a complete objection. While it was as such understandable, it would not have been sufficient for a "reasoned" decision within the meaning of Rule 111(2) EPC, but that is not an applicable standard for the communication under Rule 64(1) EPC. The incompleteness of the search division's reasoning in the present case does not by itself imply that the communication was not justified within the meaning of Rule 64(2) EPC.

Within the framework of Rule 64(2) EPC, the examining division was competent to complete the reasoning of lack of unity outlined by the search division, and did so at least in respect of the finding of lack of inventive step of original claim 1, as the reasons provided in the decision for claim 1 of the then main request (which are relied on in the reasons for Rule 64(2) EPC) followed the outline provided by the search division and addressed the claim features in sufficient detail.

32.6 However, for the reasons given at points 16.3 and 18.1 above, the board is not convinced by the reasons given by the examining division on why claim 1 of the then main request lacked an inventive step over D1 or D2 combined with D7. It follows that the board is also not convinced by the reasons given by the examining division in the context of Rule 64(2) EPC (and a fortiori by the search division) on why original claim 1 lacked an inventive step.

32.7 Furthermore, the remainder of the examining division's lack of unity reasoning (decision, point 7.2) is practically verbatim the same as that presented by the search division in sheet B, points 2 to 4 (see points 21.2 to 21.4 above), and the board considers both to be flawed.

32.7.1 Based on the finding that original claim 1 was not inventive, the examining division appears to have considered that each of the following groups of original claims,

- original claims 2-5,

- original claim 6,

- original claim 7 and 8,

- original claims 9, 12 and 13,

- original claim 10,

- original claim 11,

- original claim 14,

- original claim 15-17,

represented a group of inventions with its own "potential special technical features" and they were such that no two of them were linked with any of the others by a single general inventive concept within the meaning of Article 82 EPC.

32.7.2 The grouping of original claims 2-9, 12-13 and 15-17 into a first "search subject" and of original claims 10 and 11 into a second "search subject" was "for the search". The board assumes that this was done because searching together the claims in one of these "search subjects" did require or would have required only negligible additional work (see EPO Guidelines 2013, B-VII, 2.2).

32.7.3 Ultimately, the invitation to pay a further search fee for original claims 10 and 11 (the second "search subject") may only have been justified if these claims were non-unitary with original claims 2-9, 12-13 and 15-17 (the first "search subject").

32.7.4 The reasoning of the examining division, like that of the search division, ignores at this stage the depen­den­cies of these claims (apart from their dependency on claim 1) and appears to have only considered the additional features defined in each of the claims.

32.7.5 Original claim 10 was directed to a "method according to one of the preceding claims 3 to 9" and original claim 11 to a "method according to one of the preceding claims 3 to 10".

Hence, at least the subject-matter of original claim 3 (itself being dependent on original claim 1) was common to the first and the second "search subjects".

They may only be non-unitary if original claim 3 was not inventive, but this has neither been alleged nor established by the examining division in its reasoning on Rule 64(2) EPC.

The board notes that claim 1 of the then main request, to which the examining division referred, did include some features of original claim 3 but not all of them, for instance the step between identification and authentication of aligning the authentication features of the acquired image (essentially feature 5.4).

32.7.6 Furthermore, the examining division did not clearly spe­cify the special technical features within the meaning of Rule 44(1) EPC that characterise the first "search subject". Original claims 2-5 were said to involve "potential special features" but these were identified as "commonly known features of object recognition / authentication using a dictionary of features (BoF)", which rather suggests that these features were considered to be also not inventive over the prior art. Original claim 6 is the first claim in the first "search subject" for which more concrete "potential special features" are identified: "features of the choice of descriptors and/or geometrical relations between the keypoints solving the known problem of ensuring geometric consistency of multiple matched keypoints" (decision, point 7.2).

To be consistent with this finding, the examining division should have concluded that at least the alternatives of original claims 10 and 11 that are dependent on original claim 6 - which have been included in the second search subject - comprise the same special technical features as the first search subject, so that there is no lack of unity between the first and the second search subjects, Article 82 EPC and Rule 44(1) EPC. The examining division's reasoning is thus not consistent.

32.8 It follows that the board is not convinced by the examining division's reasoning as to why the communication pursuant to Rule 64(1) EPC was justified.

32.9 The board may now in principle either remit the case for further prosecution or exercise the power within the competence of the examining division, Article 111(1) EPC (see however T 188/00, reasons 4.6, where the board decided to immediately refund the further search fee without further reasoning after having determined that the decision of the examining division under Rule 64(2) EPC was incorrect). The board does the latter.

32.9.1 Having regard to the facts and arguments presented by the search division in the communication under Rule 64(1) EPC, the communication could only be justified if - as a minimum - original claim 3 were not inventive in view of D1 or D2 combined with D7.

32.9.2 The board does not see how such an objection of lack of inventive step on this factual basis could succeed. The objection presented by the examining division in the decision has not convinced the board. The line of argument suggested at point 18.5 above is based on D2 combined with D8, but the latter was not cited in the partial search report and cannot thus be considered in the context of Rule 64(2) EPC. Furthermore, this tentative line of argument would also fail to show that the skilled person would have arrived at the alignment step between the identification and the authentication, which is a feature of original claim 3.

32.9.3 The board has also considered whether the fact that original claim 3 fails to explicitly specify that the result of certain steps (e.g. the generation of the codebooks) are actually used in the remainder of the claim could justify disregarding the steps from the inventive step analysis (because they would as a result not contribute to a technical effect). But any objection of lack of inventive step of this kind - relying critically on clarity issues with original claim 3 - would not be "robust" in the sense of point 31.3.2 above and would also be too complex to be suitable to support an objection of lack of unity a posteriori in the context of Rule 64 EPC.

32.9.4 The board also notes that the objection of lack of inventive step outlined by the search division in the communication and its further development by the examining division in the decision were arguably already too complex and controversial to be suitable to support an objection of lack of unity of invention a posteriori in the context of Rule 64 EPC.

33. The board therefore concludes that the communication pursuant to Rule 64(1) EPC was not justified and the further search fee paid for original claims 10 and 11 is thus to be refunded, Rule 64(2) EPC.