Exhibit 5.1

Allens 33 Alfred Street Sydney NSW 2000 Australia	GPO Box 50 Sydney NSW 2001 Australia
T +61 2 9230 4000 F +61 2 9230 5333 allens.com.au	ABN 47 702 595 758

(a)

a registration statement on Form F-3 (File No. 333-284369) initially filed on January 21, 2025 and Post-Effective Amendment No. 1 on Form S-3 thereto filed with the Commission on August 28, 2025 (as so amended, the Registration Statement) under the Securities Act 1993 (U.S.), as amended from time to time (Securities Act), including the prospectus contained therein (Base Prospectus), registering certain securities, including:

(i)

ordinary shares of the Company, with no par value;

(ii)

debt securities of the Company;

(iii)

warrants of the Company;

(iv)

purchase contracts;

(v)

units; and

(vi)

subscription rights; and

(b)

a prospectus supplement relating to the registration of securities (to be issued from time to time by the Company), filed with the Commission and dated the date hereof (the Prospectus Supplement) relating to the resale of up to 11,981,668 of the Company’s ordinary shares, with no par value (the Shares) by certain shareholders named therein.

1	Definitions

(a)

ASIC means the Australian Securities and Investments Commission.

(b)

Constitution means the Amended and Restated Constitution of the Company adopted on 20 November 2025 (19 November 2025 ET) and in force as at the date of this Opinion.

(c)

Corporations Act means the Corporations Act 2001 (Cth).

 

 

 

 

We have examined and rely on originals or copies of the following documents.

 

 

 

This Opinion relates only to the laws of the Relevant Jurisdictions, as interpreted by courts of the Relevant Jurisdictions, at 9.00am (Sydney, Australia time) on the date of this Opinion.

 

This Opinion is given on the basis that it will be construed in accordance with the laws of New South Wales, Australia. Anyone relying on this Opinion agrees that this Opinion and all matters (including any liability) arising in any way from it are to be governed by the laws of New South Wales and will be subject to the non-exclusive jurisdiction of the courts of New South Wales.

 

We have not reviewed any documents other than the Documents listed in Section 2 for the purposes of this Opinion, and this Opinion does not purport to address any legal issues that arise in relation to such other documents that may be or come into force, even if there is a reference to any such documents in the Documents or on the impact such documents may have on the opinions expressed in this Opinion.

 

We have not considered and do not opine on the Registration Statement or/and any securities law disclosure requirements, other than as expressly stated herein with respect to the issue of the Shares.

 

We express no opinion as to any taxation matters or transfer pricing matters generally or liability to tax which may arise or be suffered as a result of or in connection with the Merger Agreement or on the impact which any tax laws may have on the opinions expressed in this Opinion.

 

We express no opinion on any applicable licensing or similar requirements.

 

This Opinion does not contain any undertaking to update it or to inform the Company of any changes in the laws of the Relevant Jurisdictions or any other laws which would affect the content thereof in any manner.

 

 

We have relied on the following.

 

 

We have assumed that the extracts produced by ASIC are the same as information provided by the Company to ASIC. We have not examined any documents that the Company may have filed with ASIC. The information in the extracts, or produced by the searches, may not be correct, complete or up to date.

 

We have not conducted any other searches or investigations for the purposes of this opinion.

 

 

Our opinion is as follows, subject to the assumptions in Schedule 1:

 

 

 

We are providing this Opinion in connection with the Documents and the Registration Statement. We hereby consent to the filing of this Opinion as an exhibit to the Registration Statement. In giving such consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act.

Yours faithfully

/s/ Allens

Schedule 1

 

Assumptions

 

 

 

 

 

 

 

 

 

 

 

 

 

We have not taken any step to investigate whether the assumptions in this opinion are correct, except as expressly stated in this opinion.

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IREN Completes Acquisition of Mirantis

Strengthening the Software Layer of its

Vertically Integrated AI Cloud Platform

NEW YORK, August 4, 2026 (GLOBE NEWSWIRE) – IREN Limited (NASDAQ: IREN) (“IREN”) today announced it has completed the acquisition of Mirantis, Inc. (“Mirantis”), a leading provider of cloud software and services, through the issuance of approximately 12.6m ordinary shares, fixed at signing, plus cash, restricted stock units and other consideration of approximately $40m as of closing.

The acquisition deepens IREN’s capabilities across AI workload orchestration, monitoring and customer support, further strengthening its vertically integrated AI Cloud platform spanning owned and operated data centers, compute and software.

The acquisition also supports IREN’s strategy to serve a large and diverse customer base over time, including hyperscalers, enterprises and AI developers across bare metal and managed cloud services, and has already facilitated several of IREN’s announced and prospective AI Cloud contracts.

Mirantis brings deep software engineering and technical expertise, and a track record of serving more than 1,500 enterprise customers globally. Mirantis is an inaugural partner of the NVIDIA AI Cloud Ready Initiative, and has integrated k0rdent AI with NVIDIA DSX OS software components, supporting current and next-generation NVIDIA architectures. The open-source k0rdent AI platform will continue to be developed and supported for Mirantis’ customers.

The combination brings together IREN’s owned and operated data centers and compute with Mirantis’ flexible, interoperable software layer, giving customers greater choice and control in how they deploy and scale AI workloads.

Daniel Roberts, Co-Founder and Co-CEO of IREN, commented:

“From the beginning our view has been simple: own the land and power, build the data centers, deliver the compute. Mirantis adds the software layer on top, turning infrastructure into a platform. That’s what lets us serve everyone from hyperscalers running bare metal to enterprises who want fully managed AI cloud.”

Alex Freedland, Founder and CEO of Mirantis, commented:

“For more than a decade, Mirantis has helped enterprises deploy and operate mission-critical cloud infrastructure software, and that commitment to our customers remains unchanged. Becoming part of IREN gives us the opportunity to bring those capabilities to an even larger infrastructure platform, accelerating innovation while continuing to invest in the open and infrastructure-agnostic k0rdent AI platform.”

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IREN is a vertically integrated AI Cloud provider, delivering large-scale data centers and compute for AI training and inference. IREN’s platform is underpinned by its expansive portfolio of grid-connected land and power in renewable-rich regions across North America, Europe and APAC.

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Investors

ir@iren.com

Media

media@iren.com

Forward-Looking Statements

This news release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, that involve substantial risks and uncertainties. Forward-looking statements generally relate to future events or IREN’s future financial or operating performance. Forward-looking statements include information concerning possible or assumed future results of operations, including descriptions of our business plan and strategies, revenue targets, anticipated benefits of the Mirantis acquisition, customer utilization and adoption of the k0rdent AI platform, and other trends we expect to affect our business. These statements often include words such as “anticipate,” “believe,” “may,” “can,” “should,” “could,” “might,” “plan,” “possible,” “project,” “strive,” “budget,” “forecast,” “expect,” “intend,” “target”, “will,” “estimate,” “predict,” “potential,” “continue,” “scheduled”.  Forward-looking statements may also be made, verbally or in writing, by members of our Board or management team in connection with this news release.

These forward-looking statements are based on management’s current expectations and beliefs. These statements are neither promises nor guarantees, but involve and are subject to known and unknown risks, uncertainties and other important factors that may cause IREN’s actual results, performance or achievements to differ materially from any future results performance or achievements expressed or implied by the forward-looking statements, including  IREN’s ability to successfully integrate and achieve the anticipated benefits of the acquisition, any unanticipated costs or liabilities associated with the acquisition, any failure to comply with laws, rules, regulations or business practices that IREN may become subject to as a result of any expansion of its business in connection with the acquisition of Mirantis, as well as IREN’s ability to successfully execute on its growth strategies and operating plans, achieve its targeted annualized AI Cloud revenue, continue to develop its existing data center sites, design and deploy direct-to-chip liquid cooling systems, and diversify and expand into the market for high performance computing solutions (including the market for cloud services and potential colocation services), along with other important factors discussed under the caption “Risk Factors” in IREN’s Annual Report on Form 10-K, filed with the Securities and Exchange Commission (the “SEC”) on August 28, 2025 and our other filings with the SEC. These and other important factors could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any forward-looking statement included in this press release speaks only as of the date of such statement. Except as required by law, IREN disclaims any obligation to update or revise, or to publicly announce any update or revision to, any of the forward-looking statements, whether as a result of new information, future events or otherwise.

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