# EDGAR Filing Document

**Accession Number:** 0001840678
**File Stem:** 0001104659-26-045995
**Filing Date:** 2026-4
**Character Count:** 7040
**Document Hash:** ed8d4f78576534dfd03e76cfac01107c
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-045995.hdr.sgml**: 20260421

**ACCESSION NUMBER**: 0001104659-26-045995

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20260417

**FILED AS OF DATE**: 20260421

**DATE AS OF CHANGE**: 20260421

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Lefebvre d'Ovidio Manfredi
- **CENTRAL INDEX KEY:** 0001840678

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-40777
- **FILM NUMBER:** 26879405

**MAIL ADDRESS:**
- **STREET 1:** 7 RUE DU GABIAN
- **CITY:** MONACO
- **STATE:** O9
- **ZIP:** 98000
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Arqit Quantum Inc.
- **CENTRAL INDEX KEY:** 0001859690
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-PREPACKAGED SOFTWARE [7372]
- **ORGANIZATION NAME:** 06 Technology
- **EIN:** 000000000
- **STATE OF INCORPORATION:** E9
- **FISCAL YEAR END:** 0930

**BUSINESS ADDRESS:**
- **STREET 1:** 3 ORCHARD PLACE
- **CITY:** LONDON
- **STATE:** X0
- **ZIP:** SW1H 0BF
- **BUSINESS PHONE:** 44 203 91 70155

**MAIL ADDRESS:**
- **STREET 1:** 3 ORCHARD PLACE
- **CITY:** LONDON
- **STATE:** X0
- **ZIP:** SW1H 0BF

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Lefebvre d'Ovidio Manfredi<br><sub>(Last) (First) (Middle)</sub><br>3 ORCHARD PLACE<br><sub>(Street)</sub><br>LONDON, UNITED KINGDOM SW1H 0BF<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-04-17 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [ ] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>Arqit Quantum Inc. [ ARQQ ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |  |  |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| Business Combination Warrants (right to buy) | <sup>(1)</sup> | 2026-04-17 |  | S |  |  | 151 | <sup>(1)</sup> | 2026-09-03 | Ordinary Shares | 151 | $3.1 | 28841.8 | I | Beneficially owned through Heritage Assets SCSp |
| Business Combination Warrants (right to buy) | <sup>(1)</sup> | 2026-04-20 |  | S |  |  | 307 | <sup>(1)</sup> | 2026-09-03 | Ordinary Shares | 307 | $2.8 | 28535.04 | I | Beneficially owned through Heritage Assets SCSp |

---

### Footnotes:

(1) On September 19, 2024, Arqit Quantum Inc. (ARQQ) announced the implementation of a reverse stock split whereby every 25 outstanding ARQQ ordinary shares were consolidated into one ordinary share, par value $0.0025 per share. Each Business Combination Warrant has an exercise price of $11.50 and can be exercised at any time, at the holder's election, to purchase 0.04 of an ARQQ ordinary share on a post-reverse stock split basis, and cannot be exercised for fractional shares. Accordingly, on a post-reverse stock split basis holders of Business Combination Warrants are required to exercise at least 25 Business Combination Warrants in order to receive one whole ARQQ ordinary share at an aggregate exercise price of $287.50 per whole ARQQ ordinary share. The reporting person beneficially owns 713,376 Business Combination Warrants, which, if exercised in full, would be equivalent to 28,535.04 ARQQ ordinary shares on a post-reverse stock split basis.

**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.

**Signature:** /s/ Manfredi Lefebvre d'Ovidio  
**Date:** 2026-04-21

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**