FEDERAL COURT OF AUSTRALIA Intervet International B.V. v Merial Inc [2016] FCA 1030 Appeal from: Merial, Inc v Intervet International B.V. (Federal Court of Australia, VID 399 of 2015, 16 August 2016) File number: VID 980 of 2016 Judge: MIDDLETON J Date of judgment: 24 August 2016 Catchwords: PRACTICE AND PROCEDURE – witnesses – video link – application for evidence to be given by – Federal Court of Australia Act 1976 (Cth) s 47A – whether party required to make out case for use of video link – cross-examination – overarching purpose of civil litigation – Federal Court of Australia Act 1976 (Cth) s 37(M)(1), (2), (3), (4). Legislation: Evidence Act 1995 (Cth) Evidence (Miscellaneous Provisions) Act 1958 (Vic) Federal Court of Australia Act 1976 (Cth) Patents Act 1990 (Cth) Cases cited: Australian Competition & Consumer Commission v StoresOnline International Inc [2009] FCA 717 Blackrock Asset Management Australia Services Limited v Waked (No 2) [2011] FCA 479 Campaign Master (UK) Ltd v Forty Two International Pty Ltd (No 3) (2009) 181 FCR 152 Corrigan v Commvault Systems (Aust) Pty Ltd (2011) 192 FCR 71 Decor Corp Pty Ltd v Dart Industries Inc (1991) 33 FCR 397 Director of the Fair Work Building Industry Inspectorate v Construction, Forestry, Mining and Energy Union (2015) 231 FCR 531 House v R (1936) 55 CLR 499 Neimann v Electronic Industries Ltd [1978] VR 431 Date of hearing: 24 August 2016 Registry: Victoria Division: General Division National Practice Area: Intellectual Property Sub-area: Patents and associated Statutes Category: Catchwords Number of paragraphs: 59 Counsel for the Applicant: Ms K Howard SC with Mr C Smith Solicitor for the Applicant: Spruson & Ferguson Lawyers Pty Limited Counsel for the Respondent: Mr C Dimitriadis SC with Ms C Cunliffe Solicitor for the Respondent: Ashurst Australia ORDERS VID 980 of 2016 BETWEEN: INTERVET INTERNATIONAL B.V. Applicant AND: MERIAL INC Respondent JUDGE: MIDDLETON J DATE OF ORDER: 24 August 2016 THE COURT ORDERS THAT: 1. The application for leave to appeal is dismissed with costs. Note: Entry of orders is dealt with in Rule 39.32 of the Federal Court Rules 2011. REASONS FOR JUDGMENT MIDDLETON J: INTRODUCTION 1 This is an application by Intervet International B.V. ('Intervet') for leave to appeal from a decision of the primary judge, concerning a matter of practice and procedure and the exercise of his discretion. Leave is required by s 24(1A) of the Federal Court of Australia Act 1976 (Cth) (the 'Federal Court Act') because the decision is interlocutory. The respondent, Merial Inc ('Merial') opposes the grant of leave. 2 The primary judge decided that an order should be made pursuant to s 47A of the Federal Court Act for the testimony of a particular witness, Mr Mark Pieloch, to be given by video link from the United States at the trial of the proceeding which commences next week. After considering the evidence led and the written and oral submissions made by the parties, the primary judge concluded that a 'persuasive case' had been made out for such an order. 3 In a succinct ex tempore judgment, the primary judge said: The issue before me is whether a witness proposed to be called by the appellant, namely Mr Pieloch, should be permitted to give evidence by video-link or, rather, whether the appellant should be permitted to produce Mr Pieloch for cross-examination by video-link rather than in person. There are arguments both ways. One of the arguments in favour of video evidence being permitted is that (on the basis of the information and belief evidence provided in Mr Fisher's affidavit dated today) the witness is unwilling to come. I note that Mr Pieloch has seemed to be an unwilling participant all along in this litigation, so it does not come as a surprise that he is unwilling to travel to Australia. The affidavit also refers to the fact that he has previously arranged travel over the next six weeks and he is also caring for a sibling and parent who have significant health issues; it then states that he is unable and unwilling to travel to Australia to give evidence in person at the hearing. Another factor is costs. The cross-examination is said to be likely to take half a day to one day. On the other hand, if Mr Pieloch were to travel to Australia, one is talking about four to five days of his time. But, in any event, that is probably an academic matter because the evidence is that he would not be willing to travel to Australia. Another factor is the context. Merial challenges the entitlement of Intervet. Intervet responds that it has acquired the invention from certain named inventors and names Mr Pieloch as one of these inventors. So the person who Intervet has named and identified as an inventor is the person whose evidence Merial seeks to adduce. Some of the arguments against video evidence are as follows. Mr Pieloch is a critical witness in the case. The issue of entitlement is obviously an important issue in the case and Mr Pieloch is the witness who is probably best able to give evidence about this. It is said that there are issues of credit; Intervet wishes to impugn Mr Pieloch's reliability as a witness and the reliability of the evidence that he has given. It is submitted that there are many issues that need to be explored and many documents that he will need to be taken to. Also pointed to is the lateness of the application and it is said that it should have been ascertained that there was an issue about this and the matter raised earlier. In my view, for the reasons that follow, I think a persuasive case has been made out for the evidence to be taken by video. Given that the witness, who is not in Merial's camp, is unwilling to travel to Australia, it would be unfair on the appellant to deprive it of the opportunity to rely on Mr Pieloch's evidence because he is not prepared to travel to Australia when this evidence can be adduced by video link. I do not think the difference between this evidence by video or in person is so significant in the context of the issues in this case that it provides a sufficient reason to decide that Mr Pieloch's evidence cannot be given by video. It is submitted by Intervet that the trend of authority has been against allowing video evidence and reliance has been placed, in particular, on the statements of Buchanan J in the Campaign Master (UK) case, particularly at paragraph 78. Each case, of course, depends on its own facts. Here the choice is not between the evidence being given by video or in person; the choice is between the evidence being given by video or not at all. Further, the evidence is of someone who is not in the appellant's camp. I accept that the forensic quality of the evidence by video is not as good as the evidence that can be given in person, but it all depends on the issues in the case and the circumstances more generally. The essential issue here about which Mr Pieloch is to be cross-examined is the issue of whether or not there was an assignment of an invention from his company to Intervet. Notwithstanding the respondent's submissions, it is a fairly confined issue. I note that his affidavits are only a few pages long. For completeness, I note that I accept that the application is made late and steps should have been taken earlier to ascertain if he was willing to come and if there was any controversy about his evidence being taken by video. But I need to deal with the application that is before me now and I nevertheless think, on balance, for the reasons already given, that the balance favours the evidence being given by video-link. In all the circumstances, I consider that a persuasive case has been made out for the evidence to be taken by video-link. 4 Two immediate observations can be made. The primary judge was aware of there being arguments both ways, just having the benefit of legal submissions and being aware of the evidence going to be led at trial. Secondly, the primary judge accepted that steps should have been taken to bring the application earlier but nevertheless was still able to be persuaded to make the order as requested by Merial based upon a number of factors. BACKGROUND 5 The proceeding before the primary judge is an appeal brought by Merial against a decision of the Commissioner of Patents dismissing its opposition to the grant of a patent on the patent application in suit. Intervet filed the patent application on 31 July 2009 (with a priority date of 13 August 2002), Merial filed an opposition on 28 October 2011, a decision was given on 10 July 2015 and an appeal was lodged on 31 July 2015. Subsequently, Merial amended the Notice of Appeal to introduce a new ground of lack of entitlement. 6 On 8 February 2016, the hearing of the proceeding was set down for a period of five to seven days commencing on 29 August 2016. 7 On 9 August 2016, Merial filed an Amended Interlocutory Application seeking an order that the testimony of Mr Pieloch be given by video link at the trial of the proceeding. 8 The hearing of the Amended Interlocutory Application took place on 16 August 2016. 9 Merial relied on three affidavits of Mr Fisher, filed and served on 5 August, 9 August and 16 August 2016. 10 On 16 August 2016, the parties filed submissions setting out their positions with respect to Mr Pieloch giving evidence by video link. 11 It can be accepted that Mr Pieloch is a critical witness on the issue of entitlement, and his evidence (if accepted) could be potentially fatal to Intervet's right to the grant of a patent. Mr Pieloch asserts that he is the sole inventor of the invention the subject of the patent application in suit, and that he did not agree with Intervet that it would have the rights to the invention, or that he assigned his rights to Intervet. 12 Intervet contends that it will be substantially prejudiced if it is required to cross-examine Mr Pieloch by video link because, as explained by Buchanan J in Campaign Master (UK) Ltd v Forty Two International Pty Ltd (No 3) (2009) 181 FCR 152 ('Campaign Master') at [77]-[78], the value of cross-examination is less effective if the witness is not present in the courtroom. Intervet submitted that this was especially so in the circumstances of the present case, where Mr Pieloch's evidence is crucial and involves complicated factual issues, and will involve consideration of a substantial number of lengthy documents and significant challenges to credit. RELEVANT PRINCIPLES ON APPLICATION FOR LEAVE TO APPEAL 13 Section 24(1A) of the Federal Court Act confers on the Court a discretion to grant leave to appeal. 14 The discretion of the Court in respect of an application for leave to appeal is informed by (but not limited to) the principles articulated and explained in Decor Corp Pty Ltd v Dart Industries Inc (1991) 33 FCR 397 ('Decor'). The principles are not to be applied inflexibly and each case must be considered on its own merits. 15 In Decor, the Full Court adopted (at 399) the considerations in Neimann v Electronic Industries Ltd [1978] VR 431 as 'an appropriate litmus test for the general run of cases in which leave to appeal from an interlocutory decision is sought'. Those considerations are: (1) whether, in all the circumstances, the decision is attended by sufficient doubt to warrant it being reconsidered on appeal; and (2) whether substantial injustice would result if leave were refused, supposing the decision to be wrong. 16 Where the decision appealed from involves the exercise of discretion by a trial judge (as in this instance), the Court will not interfere unless an error of the kind referred to in House v R (1936) 55 CLR 499 at 504-5 is shown to have been made. The kinds of error referred to include the following: (1) the primary judge acts upon a wrong principle; (2) he or she allows extraneous or irrelevant matters to guide or affect him or her; (3) he or she mistakes the facts; (4) he or she does not take into account some material consideration; or (5) where, if it is not possible to ascertain how a primary judge reached the result embodied in the order, and if upon the facts it is unreasonable or plainly unjust, it is appropriate to interfere upon the basis of an inference that in some way there has been a failure to properly exercise the court's discretion. 17 It is also significant to remember that the order under s 47A of the Federal Court Act of the primary judge involved a matter of practice and procedure. APPLICATION OF SECTION 47A OF THE FEDERAL COURT ACT 18 Section 47A(1) of the Federal Court Act simply provides: The Court or a Judge may, for the purposes of any proceeding, direct or allow testimony to be given by video link, audio link or other appropriate means. 19 In Campaign Master, Buchanan J considered the exercise of the power under s 47A(1) of the Federal Court Act. 20 Justice Buchanan at [78] said: I share the concerns expressed by Spender J in World Netscape and by Stone J in Dorajay about the limitation on the effectiveness of video link arrangements as a means of taking oral evidence. I am particularly troubled by the prospect (or possibility) that the cross-examination of an important witness might be rendered less effective by the limitations of video link technology or the absence of the witness from the courtroom. Although the days are gone when witnesses are expected to feel any sense of intimidation as an aid to telling the truth, there is no doubt in my mind that the requirement to give evidence on oath or affirmation in the (generally) solemn atmosphere of a courtroom in the presence of a judge, and to answer questions in cross-examination in the presence also of cross-examining counsel, has at least three potential benefits. It enhances the prospect that the witness will remain conscious of the nature and solemnity of the occasion and of his or her obligations. It affords the cross-examiner some reassurance that the gravity and immediacy of the moment, and of the supervising presence of the judge, are not lost on the witness and the cross-examination is not thereby rendered any less effective, to the possible prejudice of the cross-examining party. It provides the Court with a more satisfactory environment in which to assess the nature, quality and reliability of responses by a witness, both to questions and to the overall situation presented by the necessity to give evidence in court. To my mind there remains, even in the modern context, a certain "chemistry" in oral interchanges in a courtroom, whether between a judge and counsel (or other representative) or between cross-examiner and witness. I would not wish too lightly to deprive a cross-examiner of that traditional forensic element in the exchange although, as the cases universally make clear, the Court must now, if asked to do so, balance the interests of a cross-examining party against claimed inconvenience both in individual cases and with respect to individual witnesses. Notwithstanding the increased availability and use of video link technology, in my view, a case must be made out for the use of video link evidence if it is opposed by an affected party. I do not share the view expressed by Katz J. My own view and, I think, the weight of authority, is to the contrary. 21 In Director of the Fair Work Building Industry Inspectorate v Construction, Forestry, Mining and Energy Union (2015) 231 FCR 531 at [16], Besanko J said that the discretion given by s 47A(1) is 'a broad one with the determining consideration being the interests of justice'. In this he agreed with Flick J in Corrigan v Commvault Systems (Aust) Pty Ltd (2011) 192 FCR 71 ('Corrigan'). In that case Flick J had said (at [12]) that as 'with any exercise of discretion, reason for the exercise of the discretion must be made out by the party seeking a favourable exercise of the discretion'. 22 Justice Flick continued in the same [12] to make the following comments: Any such reason is to be found in any individual proceeding in the facts and circumstances of each proceeding and by reference to the overriding consideration of ensuring that justice is done as between the parties to that proceeding. 23 Justice Perram in Blackrock Asset Management Australia Services Limited v Waked (No 2) [2011] FCA 479 at [46] said: A trial is, in fact, a public event in which witnesses are confronted by their cross-examiners and in which they give evidence in front of the very people who are involved in the case. The giving of evidence by video link is unsatisfactory in a number of ways. That is not to say that in some cases it is not appropriate. 24 The authorities emphasise the need for a persuasive case to be made out to use a video link to take evidence. Nevertheless, the discretion conferred by legislation is unqualified. As Flick J said at [11] in Corrigan, no unnecessary gloss should be placed upon the exercise of the discretion. However, every case must be determined having in mind its context and facts. 25 Ultimately, as Edmonds J said at [14] in Australian Competition & Consumer Commission v StoresOnline International Inc [2009] FCA 717: At the end of the day, the exercise of the discretion as to what is appropriate in a particular case will involve a balancing exercise as to what will best serve the administration of justice consistently with maintaining justice between the parties. (Citations omitted.) 26 It should also not be forgotten that video link is being used in the taking of evidence in a number of contexts involving significant issues. For instance, special provisions are made for allowing the use of video link in the taking of evidence in proceedings involving children where the court takes into account the best interests of the child and the interests of justice (see, eg, s 42E and s 42F of the Evidence (Miscellaneous Provisions) Act 1958 (Vic)). It should not be assumed that in the appropriate case, even though matters of some importance are being agitated, that justice cannot be obtained by the use of video link in the taking of evidence. 27 Further, it is to be recalled that there is no right to cross-examine a witness; the obligation of the Court is to ensure a fair trial which will normally involve permitting a party to cross-examine an adverse witness. The Court has the power to control its proceedings in the course of hearing evidence (see, eg, s 11 of the Evidence Act 1995 (Cth)). Nevertheless, if a party wishes to cross-examine a witness on matters in dispute, in order for the Court to fulfil its duty to provide a fair trial, that wish would generally be granted. 28 I make this final general observation as to the operation of s 47A. Section 47A is of wide application, and can apply in these circumstances where a witness is not prepared to give oral evidence in the courtroom. Authorities contain examples where the choice is between a witness not giving evidence at all or by video link, for one reason or another. Flick J in Corrigan (at [12]) said in some cases 'a direction pursuant to s 47A(1) may indeed secure evidence that may otherwise be unavailable to one or other of the parties (and the court) by reason of the inability of a witness to attend in court.' 29 The Court is entitled to consider the legitimate interests of the party seeking to call a witness by video link. As the cases indicate the 'interests of justice' is the broad consideration. In exercising the discretion, the Court is concerned with fairness and the 'just determination' of the proceeding: see, eg, s 37(M)(2) of the Federal Court Act. Section 47A is to be read in the context of the whole of the Federal Court Act and the overarching purpose of the civil practice and procedure provisions to facilitate the 'just resolution of disputes': see s 37(M)(1), (3) and (4) of the Federal Court Act. The overriding responsibility of the Court is to provide a fair trial and to consider the interests of justice, which involves a consideration of the interests of all the parties before the Court. 30 In this case, the primary judge was confronted by a situation (which I will later more fully explain) where an important non-compellable witness would not otherwise be giving evidence relevant to an issue before the Court without permitting the use of a video link. The primary judge, nevertheless, looked at whether it was, in any event, appropriate for the evidence to be given by video link. The fact that Mr Pieloch would not be giving evidence otherwise was a relevant factor, but the primary judge went further to consider whether it was appropriate for evidence to be given by video link. In other words, the choice between no evidence given at all or by video link is a factor to be considered, but consideration still needs to be given to whether evidence via video link is appropriate. 31 It may be that in some circumstances an overwhelming case could be made that evidence by video link would be inappropriate, even if the consequence is that the witness could not be called to give evidence. That is not this case, as the primary judge decided that the evidence of Mr Pieloch could be given satisfactorily by video link. THE SUBMISSIONS OF INTERVET 32 Intervet submitted that the primary judge made two errors of principle: (1) the primary judge incorrectly approached his exercise of discretion by assuming that the onus readily shifted to Intervet to establish entitlement to the grant of a patent, such that Mr Pieloch's evidence formed a necessary part of the case that Intervet would need to put before the Court; and (2) the primary judge incorrectly approached his exercise of discretion by considering it to be a relevant consideration whether a refusal to grant leave would prejudice the s 47A applicant's ability to prosecute its case. It was contended that Merial chose to call Mr Pieloch, and the consequences of not making him available in person at the trial are not relevant to the question of whether he ought to be permitted to give evidence by video link. 33 It was contended that courts in previous decisions have been concerned to ensure that a s 47A application is not made frivolously by requiring a full and detailed explanation of why it is proposed that the witness not appear in person. It was submitted that no case has previously suggested that a relevant factor for the exercise of the discretion is that the party seeking leave would be prejudiced by not being able to adduce that evidence. 34 It was then contended that once it is established that the application has not been brought frivolously (by considering the reasons for non-attendance), the relevant assessment is whether it is appropriate for the evidence to be given by video link, by reference to the prejudice that such an approach would cause to the cross-examining party. 35 It was contended that if the new principle applied by the primary judge were to be adopted (of considering prejudice to the s 47A applicant to be relevant), an unintended result would be that future s 47A applicants would be discouraged from taking all reasonable steps to persuade a witness to attend since a refusal by an overseas witness to attend will make the grant of leave more likely, which would be a perverse outcome. 36 It was then contended that because of the primary judge's misapplication of the correct principles the primary judge gave insufficient weight to a number of relevant factors such as the importance of Mr Pieloch's evidence, the significant challenges to credit, and the number of lengthy documents on which he would need to be cross-examined. 37 It was also contended that there was not sufficient evidence to satisfy the Court as to the reasons for non-attendance and the delay in bringing the application. This was because Mr Pieloch was first advised in October 2015 of the need for him to attend a trial in Melbourne in the second half of 2016 unless an order from the Court permitting him to give evidence by video link was obtained. The trial dates were given on 8 February 2016. The primary judge had no evidence as to when Merial or its solicitors first knew that Mr Pieloch was unable and unwilling to give evidence in person at trial, and no explanation of why the application was made only two weeks before trial, and why evidence that he was unable and unwilling to attend the trial was only produced on the morning of the hearing of the application. 38 The primary judge also had no direct evidence from Mr Pieloch as to his inability and unwillingness to attend, but only statements based on information from the US attorney for Merial obtained in a phone call with Mr Pieloch and then in turn passed on in a summarised form to Merial's solicitor, Mr Fisher, who swore the supporting affidavit on the day of the application before the primary judge as follows: I am informed by Mr Kowalski, and I believe, the following matters in relation to Mr Pieloch: (a) Mr Kowalski spoke with Mr Pieloch on 15 August 2016 and was informed of the following matters. (b) Mr Pieloch has previously arranged travel over the next six weeks and is also caring for a sibling and parent who have significant health issues. (c) Mr Pieloch is unable and unwilling to travel to Australia to give evidence in person at the appeal hearing. (d) Mr Pieloch is willing to give evidence at the appeal hearing by video link from the United States. Mr Pieloch will provide details of his availability shortly. 39 On this basis, Intervet contended that the absence of any evidence that explained these matters in circumstances where there was an obligation to make inquiries of the witnesses at as early a stage a possible ought to have weighed heavily against granting leave for Mr Pieloch to give evidence by video link. 40 It was contended that the evidence relied upon by Merial did not satisfy the standard required by courts in an application such as the present one, and this should have been taken into account. Those considerations should have supported the conclusion that it was unfair for Intervet to be deprived of the opportunity of having Mr Pieloch give evidence in person, rather than it being unfair for Merial not to have the opportunity to rely on the evidence of Mr Pieloch. CONSIDERATION Sufficient doubt 41 It is to be recalled that Mr Pieloch is named by Intervet as an inventor in support of its application for a patent, which is opposed by Merial in the proceeding below under the provisions of the Patents Act 1990 (Cth) (the 'Act'). Thus Intervet is the party who has had a prior relationship with Mr Pieloch, and then claims to derive its title to the alleged invention from him. Mr Pieloch is not in Merial's camp, and Merial has no prior relationship with him. Mr Pieloch is not a compellable witness. 42 There is no dispute that Mr Pieloch was an inventor of the alleged invention claimed in the patent application, if the invention was patentable. An essential issue (but not the only issue) to which Mr Pieloch's evidence goes is whether or not there was any assignment of rights in that invention from Mr Pieloch to Intervet, as Intervet asserts in support of its claim to be entitled to the grant of a patent. There is another issue relating to whether Mr Pieloch was in reality the sole inventor who conceived of and developed the invention. This issue is pleaded by Merial, and Mr Pieloch refers to this in his affidavit of 20 January 2016. Whilst reference was made in submissions by Merial to the 'confined nature' of the issues for cross-examination, the primary judge had all the evidence of Mr Pieloch before him, and would have made his own assessment based on that evidence. The primary judge was entitled to proceed on the basis of his assessment that the testimony was relatively confined and based upon documentation. 43 There was admissible evidence before the primary judge to the effect that Mr Pieloch was unable and unwilling to travel to Australia to give oral testimony. The primary judge was entitled to accept that evidence. The fact the evidence to this effect was produced late was observed by the primary judge, but this did not affect the admissibility of the evidence. 44 The primary judge then had this position before him: Mr Pieloch was a person from whom Intervet claimed to derive its title to the alleged invention, who was not in Merial's camp or under its control, whose evidence was clearly relevant but nevertheless seemed confined in scope, and who, on the evidence, would not come to Australia for the hearing and could not be compelled to do so. 45 The primary judge concluded that the choice in this case was not between Mr Pieloch's evidence being given by video link or in person, but rather between it being given by video link or not at all. However, that was not the only matter that the primary judge considered. In addition, the primary judge decided that the difference between video link and live testimony was not 'so significant in the context of the issues in this case that it provides a sufficient reason to decide that Mr Pieloch's evidence cannot be given by video'. 46 The primary judge considered each relevant factor, weighed up the competing considerations, and exercised his discretion accordingly. I can see no error in that approach or in his decision. The primary judge was entitled to consider the interests of Merial in seeking to call its witness to support its own case, on the basis of the authorities I have referred to above. The overriding consideration is the interests of justice. 47 I now turn to consider some of the specific matters raised by Intervet. Intervet asserts that the primary judge 'erred in his approach to the question of onus on the issue of entitlement to a patent, which led him to grant leave' for Mr Pieloch to give evidence by video link. The primary judge did not discuss in his reasons 'onus'. He realised Merial needed to adduce evidence, and the transcript shows the primary judge was aware the legal onus was on Merial. I do not consider that any other comments in the transcript of the primary judge indicate that he was not aware of this position. In the course of argument, the primary judge was mindful of the fact that Merial, as the opponent under s 59 of the Act, had the onus of establishing each ground of opposition. There is nothing in the primary judge's reasons or approach to suggest that the primary judge regarded the legal onus on this ground as not resting on Merial. In any event, the question of onus did not lead the primary judge to grant leave under s 47A, as Intervet asserts. The primary judge granted leave taking into account all of the facts and circumstances of the case. There was no one single consideration that was determinative over all others. 48 Intervet also asserts that the primary judge 'erred in applying the relevant principles in exercising the discretion under s 47A'. The primary judge was taken in detail to the applicable principles during the course of the hearing. He referred to them in his ex tempore reasons, by reference to the decision of Buchanan J in Campaign Master on which Intervet relied. He correctly applied those principles, by considering whether a persuasive case had been made out for an order for video link testimony. 49 Intervet then asserts that the primary judge 'erred in finding and holding that the evidence of Mr Pieloch was confined to the issue of whether there was an assignment of an invention from his company to Intervet', and that the length of his affidavits was 'not a relevant consideration'. 50 I have already touched upon this issue. The primary judge observed that the 'essential issue' about which Mr Pieloch was to be cross-examined was the issue of whether or not there was an assignment as asserted by Intervet. This seems a reasonable approach. There is no dispute between the parties that Mr Pieloch was an inventor of the alleged invention. The primary judge was taken to the evidence to be adduced by Mr Pieloch. He was aware of its extent. I will assume the primary judge was fully aware of all the material before him, and in giving his ex tempore reasons had that material clearly in contemplation in the course of giving those reasons. It may be the length of the affidavit is no absolute indication of the extent of cross-examination, but this was just an indicator. This indication did not dictate the result to which the primary judge finally reached, and does not otherwise affect the correctness of his ultimate decision. 51 In view of the above, I conclude that the decision of the primary judge was not attended by sufficient doubt to warrant it being reconsidered on appeal. Substantial injustice 52 I make some comments upon the issue of substantial injustice, although I would dispose of this application for leave to appeal because there has not been shown to be sufficient doubt in the decision of the primary judge to warrant reconsideration on appeal. 53 Intervet submitted that substantial injustice will result from refusal of leave to appeal because, if the decision sought to be appealed is wrong, Intervet will be denied the opportunity to cross-examine Mr Pieloch in person in circumstances where cross-examination by video link would cause substantial prejudice to Intervet. It relied upon the importance of the evidence, the amount of documentation involved and the need to address credit. 54 Intervet submitted that to the extent that the prejudice to Intervet's ability to effectively cross-examine Mr Pieloch were to result in a finding of lack of entitlement, it would be a final determination of Intervet's rights. If failing to secure the attendance of Mr Pieloch in Australia at the trial deprived Merial of its ability to support its lack of entitlement ground, Merial would have the opportunity to subsequently raise that ground in seeking to revoke the patent post-grant. 55 Finally, it was submitted that if leave to appeal is not granted, and Intervet is left to pursue any appeal at a later time following a final decision in the present appeal, it would be difficult to determine the impact of Mr Pieloch's evidence being given by video link rather than in person at the hearing in any such appeal. 56 In answer to these submissions I make these observations. 57 The primary judge made the interlocutory decision under s 47A as the docket judge, exercising a discretion. It was a matter of practice and procedure. The primary judge at trial will be able to determine, if and when Mr Pieloch gives evidence, whether to allow the video link evidence to continue, and what weight to accord to the evidence, taking into account how the cross-examination actually proceeds. There is no reason why (if the circumstances are such as to warrant it) the primary judge could not revoke or vary the order made under s 47A. There is always the possibility (for instance) that there is a failure of the video link itself, that documentation is not satisfactorily prepared for the overseas witness to address, or the extent and nature of the actual questions asked by the cross-examiner require the 'more satisfactory environment' mentioned by Buchanan J in Campaign Master. So if it became apparent to the primary judge during the cross-examination that the cross-examiner was at such a disadvantage (in view of the actual issues being canvassed with the witness) that it would be unfair to proceed by video link, the primary judge can intervene to ensure a fair trial at that stage of the trial. 58 In my view, in addition to there being no error shown in the approach of the primary judge, there is also no substantial injustice resulting by the failure to grant leave to appeal. CONCLUSION 59 For the above reasons the application for leave to appeal will be dismissed with costs. I certify that the preceding fifty-nine (59) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Middleton. Associate: Dated: 24 August 2016