Can I legally get evidence from a competitor who I suspect is infringing my intellectual property?
You can use the "preliminary discovery" process to obtain documents prior to the commencement of court proceedings to assess the merits of a potential claim on the grounds that you have a reasonable belief that you may have the right to obtain relief from a prospective respondent.
In the case of Pfizer Ireland Pharmaceuticals v Samsung Bioepis AU Pty Ltd  FCAFC 193 Pfizer was concerned that the manufacture of BRENZYS by Samsung Bioepis AU Pty Ltd might infringe one or more of Pfizer's process patents for ENBREL. However, it did not have sufficient information to decide whether to commence patent infringement proceedings. Pfizer used the Federal Court's preliminary discovery procedure to obtain documents that SBA lodged with the Therapeutic Goods Administration regarding the processes used to make BRENZYS.
Rule 7.23 of the Federal Court Rules 2011 (Cth) allows a prospective applicant to apply to the Court for an order for discovery by a prospective respondent if the prospective applicant:
(a) has a reasonable belief that it has the right to obtain relief in the Court from a prospective respondent;
(b) after making reasonable inquiries, does not have sufficient information to decide whether to start proceedings to obtain such relief; and
(c) reasonably believes that the prospective respondent has, or is likely to have, in its control documents directly relevant to the right to obtain the relief, and that inspection of the documents would assist in making the decision.
Justice Burley initially refused Pfizer's application because he was not satisfied that Pfizer demonstrated that it had a "reasonable belief", as opposed to a "mere suspicion". On appeal, the Full Court held that the evidence presented by Pfizer was sufficient to establish that it had a reasonable belief that it may have a right to obtain relief from SBA for patent infringement. SBA was ordered to provide the discovery sought by Pfizer.
Justice Perram provided the following rules in relation to preliminary discovery:
(a) the prospective applicant must prove that it has a belief that it may (not does) have a right to relief;
(b) the prospective applicant must demonstrate that the belief is reasonable, either by reference to material known to the person holding the belief, or by other material subsequently placed before the Court;
(c) a person deposing to the belief need not give evidence of the belief a second time, to the extent that additional material is placed before the Court on the issue of the reasonableness of the belief;
(d) the question of whether the belief is reasonable requires asking whether a person apprised of all of the relevant material could reasonably believe that they may have a right to obtain relief;
(e) one may believe that a person may have a case on certain material without one's mind being in any way inclined to the notion that they do have such a case; and
(f) in practice, in order to defeat a claim for preliminary discovery, it will be necessary either to show that the subjectively held belief does not exist or, if it does, that there is no reasonable basis for thinking that there may be (not is) such a case.