Andrew Leaver - 05 Oct 2026 Form 4 Insider Report for Arqit Quantum Inc. (ARQQ)

Reporting relationship: Chief Executive Officer
Issuer ticker: ARQQ
Reported as of: 05 Oct 2026
Net transaction value: -$60,294
SEC form: 4
Accepted by SEC: 07 Oct 2026, 19:52:58 UTC
Prior SEC filing: 06 Oct 2026
Next SEC filing: 08 Oct 2026
Source filing: View source filing
Reporting owner signature: /s/ Noleen McDonnell, as Attorney-in-Fact

Key filing fact

Andrew Leaver filed Form 4 for Arqit Quantum Inc. (ARQQ) on 07 Oct 2026.

Key facts

This page summarizes Andrew Leaver's Form 4 filing for Arqit Quantum Inc. (ARQQ).
6 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 07 Oct 2026, 19:52.

Change

Previous filing in this sequence was filed on 06 Oct 2026.
Current net transaction value: -$60,294.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0002035890 Primary reporting owner

Leaver Andrew

Relationship: Chief Executive Officer
Address: 3 ORCHARD PLACE, LONDON, UNITED KINGDOM
Signature: /s/ Noleen McDonnell, as Attorney-in-Fact
Signature date: 07 Oct 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

ARQQ transaction

Ordinary Shares

Sale

Transaction value: $60,294
Shares: -2,535
Change %: -4.3%
Price: $23.78
Shares after: 56,547
Date: 05 Oct 2026
Ownership: Direct

ARQQ transaction

Ordinary Shares

Other

Transaction value
Shares: -5,209
Change %: -9.2%
Price: $0.000000^*
Shares after: 51,338
Date: 05 Oct 2026
Ownership: Direct
Footnotes: F1, F2

ARQQ transaction

Ordinary Shares

Options Exercise

Transaction value
Shares: +5,208
Change %: +10%
Price: $0.000000^*
Shares after: 56,546
Date: 05 Oct 2026
Ownership: Direct
Footnotes: F2

ARQQ transaction

Ordinary Shares

Other

Transaction value
Shares: -2,818
Change %: -5%
Price: $24.47^*
Shares after: 53,728
Date: 05 Oct 2026
Ownership: Direct
Footnotes: F1, F3

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

ARQQ transaction Derivative

Restricted Share Units

Other

Transaction value
Shares: +5,209
Change %: +2.7%
Price: $0.000000^*
Shares after: 197,917
Date: 05 Oct 2026
Ownership: Direct
Underlying class: Ordinary Shares
Underlying amount: 5,209
Exercise price
Footnotes: F1, F2, F4

ARQQ transaction Derivative

Restricted Share Units

Options Exercise

Transaction value
Shares: -5,208
Change %: -2.6%
Price: $0.000000^*
Shares after: 192,709
Date: 05 Oct 2026
Ownership: Direct
Underlying class: Ordinary Shares
Underlying amount: 5,208
Exercise price
Footnotes: F4

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 4 footnotes

Footnote F1

This trade cancelled out the transaction from October 2, 2026 to correct the applicable tax rate and number of units required to be sold in a sell-to-cover transaction.

Footnote F2

The Restricted Share Units ("RSUs") convert into ARQQ ordinary shares on a one-for-one basis.

Footnote F3

The price for acquiring these ordinary shares is the same price that the units were sold for on October 2.

Footnote F4

The RSUs vest quarterly in equal installments on October 1, 2026, and January 1, April 1, July 1, and October 1, 2027, and January 1, April 1, July 1, and October 1, 2028, and January 1, April 1, July 1, and October 1, 2029.

SEC remarks

Due to the Issuer's status as a foreign private issuer pursuant to Rule 3a12-3(b) under the Securities Exchange Act of 1934 (the "Act"), the reporting person's transactions in the Issuer's securities are exempt from Sections 16(b) and 16(c) of the Act.