# EDGAR Filing Document

**Accession Number:** 0001896084
**File Stem:** 0001140361-25-035847
**Filing Date:** 2025-9
**Character Count:** 5958
**Document Hash:** 9ec3b8be649d83c89611f15721285d26
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001140361-25-035847.hdr.sgml**: 20250923

**ACCESSION NUMBER**: 0001140361-25-035847

**CONFORMED SUBMISSION TYPE**: 6-K

**PUBLIC DOCUMENT COUNT**: 6

**CONFORMED PERIOD OF REPORT**: 20250923

**FILED AS OF DATE**: 20250923

**DATE AS OF CHANGE**: 20250923

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ioneer Ltd
- **CENTRAL INDEX KEY:** 0001896084
- **STANDARD INDUSTRIAL CLASSIFICATION:** MINING, QUARRYING OF NONMETALLIC MINERALS (NO FUELS) [1400]
- **ORGANIZATION NAME:** 01 Energy & Transportation
- **EIN:** 000000000
- **STATE OF INCORPORATION:** C3
- **FISCAL YEAR END:** 0630

**FILING VALUES:**
- **FORM TYPE:** 6-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-41412
- **FILM NUMBER:** 251333670

**BUSINESS ADDRESS:**
- **STREET 1:** 140 ARTHUR STREET
- **STREET 2:** SUITE 5.03, LEVEL 5
- **CITY:** NORTH SYDNEY
- **STATE:** C3
- **ZIP:** NSW 2060
- **BUSINESS PHONE:** 61(2)99225800

**MAIL ADDRESS:**
- **STREET 1:** 140 ARTHUR STREET
- **STREET 2:** SUITE 5.03, LEVEL 5
- **CITY:** NORTH SYDNEY
- **STATE:** C3
- **ZIP:** NSW 2060

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#### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549

#### <br>

### FORM 6-K

#### <br>

#### REPORT OF FOREIGN PRIVATE ISSUER

#### Pursuant to Rule 13a-16 or 15d-16 of the

#### Securities Exchange Act of 1934

#### For the month of September 2025
**** 

<br> **Commission File Number:**001-41412

**** 

<br> ## ioneer Ltd
(Translation of registrant's name into English)<br>

#### <br>

#### Suite 16.01, 213 Miller Street

#### North Sydney, NSW, 2060, Australia
(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒ Form 40-F ☐

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#### EXHIBIT INDEX
The following exhibits are filed as part of this Form 6-K:

<u> Exhibit </u> <u> Description </u> <br> <br> [99.1](ef20055935_ex99-1.htm) Press Release

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#### SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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| | | |
|:---|:---|:---|
|  | ioneer Ltd | ioneer Ltd |
|  | (registrant) | (registrant) |
| Date: September 23, 2025 | By: <br>| /s/ Ian Bucknell  |
|  | Name: Ian Bucknell | Name: Ian Bucknell |
|  | Title: Chief Financial Officer & Company Secretary | Title: Chief Financial Officer & Company Secretary |

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## Exhibit 99.1

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 **Exhibit 99.1**<br>

**** 

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| ![](image00001.jpg) | ![](image00005.jpg) |
| ![](image00001.jpg) | ![](image00005.jpg) |
| ![](image00001.jpg) | ![](image00005.jpg) |
| ![](image00001.jpg) | ![](image00005.jpg) |
| ![](image00001.jpg) | ![](image00005.jpg) |
| ![](image00001.jpg) | ![](image00005.jpg) |

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## Ioneer Announces Departure of Chief Financial Officer
**22 September 2025** – **Ioneer Ltd ("Ioneer") (ASX: INR, NASDAQ: IONR)** today announced that Ian Bucknell, Chief Financial Officer (CFO) and Company Secretary, will be departing the Company to pursue other interests, effective mid-December. This comes after seven years of service with the company and marks a transition point for the company as his replacement will be U.S. based.

Ian will continue in his current roles through his contractual notice period, ensuring business continuity and a smooth transition of the CFO and Company Secretarial roles and responsibilities. This transition will allow Ian to assist with the completion of the results season, including the 20-F for U.S. reporting purposes, and preparation of the AGM.

As Ioneer looks forward to completing the strategic partnering process, final investment decision (FID) and construction of the Rhyolite Ridge Project in Nevada, the company intends to relocate the CFO role to the U.S. to ensure strong financial leadership and cost control for the project and finance team. The Company Secretarial role will remain in Australia.

Ioneer Managing Director Bernard Rowe said "We would like to thank Ian for his significant contribution to the company over these past seven years. His expertise, professionalism and unwavering commitment have been instrumental in positioning our business well for the future. We wish him every success in his next endeavour."

This ASX release has been authorised by Ioneer Managing Director, Bernard Rowe.

#### --ENDS—

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| | | |
|:---|:---|:---|
| Investor Relations | Investor Relations | Media Relations |
|  | **Chad Yeftich**<br> **Ioneer USA Corporation** | **Daniel Francis**<br> **FGS Global (USA)** |
|  | Investor Relations (USA)<br> T: +1 775 993 8563<br> E: <u>ir</u><u>@ioneer.com</u> | Media Relations (AUS)<br> E: <u>daniel.francis@fgsglobal.com</u> |

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![](image00004.jpg)

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### About Ioneer
Ioneer Ltd is an emerging lithium–boron producer and the 100% owner of the Rhyolite Ridge Lithium-Boron Project. Rhyolite Ridge is one of only a small number of lithium-boron ore deposits globally, and a linchpin project in Nevada's burgeoning Lithium Loop.

Rhyolite Ridge closed a US$996 million loan with the U.S. Department of Energy Loan Programs Office under the Advanced Technology Vehicles Manufacturing program in January 2025. In October 2024, Ioneer received the final federal permit for the project from the Bureau of Land Management, concluding the formal federal permitting process which began in early 2020. Ioneer signed separate offtake agreements with Ford Motor Company and Prime Planet & Energy Solutions (joint venture between Toyota and Panasonic) in 2022 and Korea's EcoPro Innovation in 2021.

To learn more about Ioneer, visit <u>www.Ioneer.com/investors</u> or join our online communities on <u>X</u>, <u>Facebook</u>, <u>LinkedIn</u>, <u>Instagram</u> and <u>YouTube</u>

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| 2 | ![](image00004.jpg) |

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