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Accumulated Losses and Reserves - Summary of Accumulated Losses and Reserves (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2023
Disclosure Of Reserves Within Equity [Line Items] |  |  |
Net loss for the period | $ (162,791) | $ (220,242) | $ (142,521)
Total reserves | 43,938 | 37,809 |
Movements in Accumulated Losses |  |  |
Disclosure Of Reserves Within Equity [Line Items] |  |  |
Beginning balance | (579,704) | (359,462) |
Net loss for the period | (162,791) | (220,242) |
Ending balance | (742,495) | (579,704) | (359,462)
Reserves |  |  |
Disclosure Of Reserves Within Equity [Line Items] |  |  |
Fair value of Investments reserve | 1,085 | 1,085 |
Share-based payments reserve | 22,764 | 16,636 |
Foreign translation reserve | 20,089 | 20,089 |
Total reserves | 43,938 | 37,810 |
Movement in Fair Value of Investments Reserve |  |  |
Disclosure Of Reserves Within Equity [Line Items] |  |  |
Opening balance | 1,085 | 1,085 |
Closing balance | 1,085 | 1,085 | 1,085
Movement in Share-Based Payments Reserve |  |  |
Disclosure Of Reserves Within Equity [Line Items] |  |  |
Opening balance | 16,636 | 11,551 |
Share-based payments reserve | 6,128 | 5,085 |
Closing balance | 22,764 | 16,636 | 11,551
FX Translation Reserve |  |  |
Disclosure Of Reserves Within Equity [Line Items] |  |  |
Opening balance | 20,089 | 20,089 |
Closing balance | $ 20,089 | $ 20,089 | $ 20,089

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