# EDGAR Filing Document

**Accession Number:** 0001952901
**File Stem:** 0001104659-26-076832
**Filing Date:** 2026-6
**Character Count:** 40743
**Document Hash:** 992607aa0ab4858403bce03a484d28d8
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-076832.hdr.sgml**: 20260623

**ACCESSION NUMBER**: 0001104659-26-076832

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D/A

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20260623

**DATE AS OF CHANGE**: 20260623

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MILLICOM INTERNATIONAL CELLULAR SA
- **CENTRAL INDEX KEY:** 0000912958
- **STANDARD INDUSTRIAL CLASSIFICATION:** RADIO TELEPHONE COMMUNICATIONS [4812]
- **ORGANIZATION NAME:** 06 Technology
- **EIN:** 000000000
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-49833
- **FILM NUMBER:** 261111436

**BUSINESS ADDRESS:**
- **STREET 1:** 148-150, BOULEVARD DE LA PETRUSSE
- **CITY:** LUXEMBOURG
- **STATE:** N4
- **ZIP:** L-2330
- **BUSINESS PHONE:** 3524571451

**MAIL ADDRESS:**
- **STREET 1:** 148-150, BOULEVARD DE LA PETRUSSE
- **CITY:** LUXEMBOURG
- **STATE:** N4
- **ZIP:** L-2330
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Atlas Investissement SAS
- **CENTRAL INDEX KEY:** 0001952901

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** I0
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A

**BUSINESS ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** 16 RUE DE LA VILLE L'EVEQUE
- **CITY:** PARIS
- **PROVINCE COUNTRY:** I0
- **BUSINESS PHONE:** 33 1 42 66 99 19

**MAIL ADDRESS:**
- **ADDRESS IS A NON US LOCATION:** YES
- **STREET 1:** 16 RUE DE LA VILLE L'EVEQUE
- **CITY:** PARIS
- **PROVINCE COUNTRY:** I0

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Atlas Investissement
- **DATE OF NAME CHANGE:** 20221031

## Exhibit 99.63

**Exhibit 99.63**

**AMENDMENT AGREEMENT** 

**dated 18 June 2026**

**to a Share Swap Transaction dated 11 March 2026 and amended on 27 March 2026**

**Between:**

**SOCIÉTÉ GÉNÉRALE,** a company incorporated in accordance with the laws of France, with registered address at 29 Boulevard Haussmann, 75009 Paris, France, recorded with the Commercial Registry of Companies under number 552.120.222 and ADEME number FR231725_01YSGB ("**Bank**"). The company is duly represented by [Olivier Buttier].

**And:**

**ATLAS INVESTISSEMENT S.A.S.** a company incorporated in accordance with the laws of France, with registered address at 16 rue de la Ville L'Evêque 75008 Paris, France, recorded with the "*Registre du Commerce et des Sociétés*" of Paris under number 908 070 188 ("**Counterparty**"**)**. The company is duly represented by Xavier Rioult de Neuville.

1.1 This amendment agreement ()"**Amendment**") is made and entered into between Bank and Counterparty,
hereinafter referred to individually as a "Party" and collectively the "Parties".

1.2 Whereas Bank and Counterparty entered into a **Share Swap Transaction** on March 11<sup>th</sup>, 2026
(the "**Transaction** "), evidenced by a confirmation date March 11<sup>th</sup>, 2026 (the "**Confirmation** ")
governed by an ISDA Master Agreement dated as of March 11<sup>th</sup>, 2026 (the "**Master Agreement** "), each as amended,
supplemented or otherwise modified from time to time.

1.3 Whereas Bank and Counterparty desire to amend the Transaction.

Accordingly, in consideration of the mutual agreements contained in this Amendment the Parties agree as follows:

1. Amendments to Transaction

Bank and Counterparty hereby agree that, upon execution of this Amendment by both Parties, and subject to Article 2 below, with effect from the date hereof (the "**Second Amendment Effective Date**"):

1.1 the definition of the term "**Maximum Equity Notional Amount**" and "**Maximum Number of Shares"** in the Section "*General Terms*" in the Confirmation (including for the avoidance of doubt its Annexes)
is hereby amended and restated in its entirety as set out in Appendix 2 (*Amended Definition*) hereto.

1.2 the definition of the term "**Maximum Number of Shares"** in the Section "*General Terms*" in the Confirmation (including for the avoidance of doubt its Annexes) is hereby amended and restated in its entirety
as set follows:

"**Maximum Number of Shares:** 

*Means:*

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*(i)* *from the Exchange Business Day following the Second Amendment Effective Date (included) to the Termination Date (included), a number of Shares equal to the sum of (x) 4,500,000 and (y) the Residual Number of Shares(1);* 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*(ii)* *from March 27<sup>th</sup>, 2026 (excluded) until the Second Amendment Effective Date (included) a number of Shares equal to the sum of (x) 3,250,000 and (y) the Residual Number of Shares(1); and* 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;*(iii)* *from the Trade Date (included) until March 27<sup>th</sup>, 2026 (included), the "Maximum Number of Shares" set out in the Original Confirmation."* 

1.3 the definition of the term "Settlement Date(2)" set out in Annex 1 of the Confirmation is
hereby amended to refer to 29 June 2026.

2. Conditions precedent

The entry into force of the Amendment is subject to the elements listed in Appendix 1 (*Conditions precedent*) hereto, in each case in a form and substance satisfactory to Bank on the date hereof.

3. Continuity and further assurance

3.1 Continuing obligations

Except for any amendment to the Transaction and the Confirmation made pursuant to this Amendment, all terms and conditions of the Transaction, the Confirmation and the Master Agreement will continue in full force and effect in accordance with their provisions on the Second Amendment Effective Date.

3.2 Further assurance

Counterparty shall at its own expense, do all acts and steps necessary or desirable to give effect to the amendments effected or to be effected by this Amendment.

4. Representations

Counterparty repeats as of the date hereof the representations made to Bank in Sections 6.1(a), 6.1(h) and 6.1(i) of the Confirmation provided that reference therein to "this Transaction" shall be deemed to be reference to this Amendment. Each Party repeats as of the date hereof the representations made by it to the other Party in Sections 3(a), 3(b), 3(c), 3(d), 3(e) and 3(g) of the Agreement.

5. Miscellaneous

(a)  ***<u>Entire Agreement; Restatement</u>*** . This Amendment constitutes the entire agreement and
understanding of the Parties with respect to its subject matter and supersedes all oral communication and prior writings (except as otherwise
provided herein) with respect thereto.

(b)  ***<u>Amendments</u>*** . No amendment, modification or waiver in respect of the matters contemplated
by this Amendment will be effective unless made in accordance with the terms of the Master Agreement.

(c)  ***<u>Counterparts</u>*** . This Amendment may be executed and delivered in counterparts, each
of which will be deemed an original.

(d)  ***<u>Headings</u>*** . The headings used in this Amendment are for convenience of reference only
and are not to affect the construction of or to be taken into consideration in interpreting this Amendment.

**(e)**  ***<u>Governing law & Jurisdiction</u>*** . This Amendment and any non-contractual obligations
arising out of or in connection with it are governed by and construed in accordance with English law. The provisions of Clause 13(b) (*Jurisdiction*)
of the Master Agreement shall apply to this Amendment as it applies to the Master Agreement.

**IN WITNESS** whereof the Parties have executed this Amendment on the respective date specified below with effect from the Second Amendment Effective Date.

On the 18 of June 2026, in Paris.

**ATLAS INVESTISSEMENT S.A.S.**

---

| | |
|:---|:---|
| By: | /s/ Xavier RIOULT DE NEUVILLE |
| **Name:** | **Xavier RIOULT DE NEUVILLE** |
| Title: | Directeur Général |

---

**SOCIÉTÉ GÉNÉRALE**

---

| | |
|:---|:---|
| By: | /s/ Olivier BUTTIER |
| Name: | **Olivier Buttier** |
| Title: | Head of Strategic Transactions Group |

---

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

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**(Amendment No. 28)**

**MILLICOM INTERNATIONAL CELLULAR SA**

*(Name of Issuer)*

**Common Shares**

*(Title of Class of Securities)*

**—**

*(CUSIP Number)*

**Denis Klimentchenko**<br>Skadden, Arps, Slate, Meagher & Flom<br>(UK) LLP, 22 Bishopsgate<br>London X0 EC2N 4BQ<br>44(0)20 7519 7289

*(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)*

**06/18/2026**

*(Date of Event Which Requires Filing of this Statement)*

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Atlas Investissement SAS** | Name of reporting person<br>**Atlas Investissement SAS** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**CO** | Type of Reporting Person (See Instructions)<br>**CO** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 common shares, par value $1.50 per share ("Common Shares") of Millicom International Cellular S.A., a Luxembourg company (the "Issuer"), referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement SAS, a company incorporated under French law as a societe par actions simplifiee ("Atlas Investissement"), plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements (as defined in Item 4 below) on June 29, 2026. Iliad Holding SAS ("Iliad Holding"), as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya SAS ("Maya"), as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. Xavier Niel, the President of Maya, Jules Niel, John Niel, Elisa Niel and Joseph Niel (together, the "Niel Family") may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Iliad Holding SAS** | Name of reporting person<br>**Iliad Holding SAS** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**CO** | Type of Reporting Person (See Instructions)<br>**CO** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 Common Shares, referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement, plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements on June 29, 2026. Iliad Holding, as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya, as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. The Niel Family may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Maya SAS** | Name of reporting person<br>**Maya SAS** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**CO** | Type of Reporting Person (See Instructions)<br>**CO** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 Common Shares, referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement, plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements on June 29, 2026. Iliad Holding, as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya, as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. The Niel Family may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Xavier Niel** | Name of reporting person<br>**Xavier Niel** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 Common Shares, referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement, plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements on June 29, 2026. Iliad Holding, as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya, as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. The Niel Family may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Jules Niel** | Name of reporting person<br>**Jules Niel** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 Common Shares, referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement, plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements on June 29, 2026. Iliad Holding, as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya, as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. The Niel Family may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**John Niel** | Name of reporting person<br>**John Niel** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 Common Shares, referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement, plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements on June 29, 2026. Iliad Holding, as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya, as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. The Niel Family may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Elisa Niel** | Name of reporting person<br>**Elisa Niel** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 Common Shares, referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement, plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements on June 29, 2026. Iliad Holding, as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya, as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. The Niel Family may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Joseph Niel** | Name of reporting person<br>**Joseph Niel** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[ ] (a)<br>[x] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**I0** | Citizenship or place of organization<br>**I0** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**78320018.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**78320018.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | Aggregate amount beneficially owned by each reporting person<br>**78320018.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**46.7%** | Percent of class represented by amount in Row (11)<br>**46.7%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

**Comment for Reporting Person:** (1) Reflects 77,070,018 Common Shares, referred to herein on the same basis as disclosed in Amendment Nos. 26 and 27 to the Schedule 13D, beneficially owned by Atlas Investissement, plus 1,250,000 additional Common Shares that Atlas Investissement expects to purchase under the Amended Equity Derivative Transaction Agreements on June 29, 2026. Iliad Holding, as the controlling shareholder of Atlas Investissement, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement. Maya, as the controlling shareholder of Iliad Holding, may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Iliad Holding and Atlas Investissement. The Niel Family may be deemed to have shared beneficial ownership over the Common Shares beneficially owned by Atlas Investissement, Iliad Holding and Maya.

(2) The percentage reflected in row 13 in the table above is calculated on the basis of 167,707,493 Common Shares outstanding as of May 31, 2026 (169,000,000 Common Shares outstanding, less 1,292,507 Common Shares held in treasury), as set forth in the last relevant update available on the date hereof on the Issuer's website.

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Common Shares

**(b) Name of Issuer:**
MILLICOM INTERNATIONAL CELLULAR SA

**(c) Address of Issuer's Principal Executive Offices:**
8400 NW 36th Street, Suite 530, Doral, FL, 33166

This Amendment No. 28 ("Amendment No. 28") to Schedule 13D relates to the Common Shares, par value $1.50 per share (the "Common Shares"), of Millicom International Cellular S.A., a Luxembourg company ("Issuer"), and amends and supplements the initial statement on Schedule 13D filed on February 24, 2023, as previously amended (as so amended, the "Schedule 13D"). Capitalized terms used but not defined in this Amendment No. 28 shall have the same meanings ascribed to them in the Schedule 13D.

**Item 4. Purpose of Transaction**

Item 4 of the Schedule 13D is hereby amended and supplemented by adding the following:

On June 18, 2026, Atlas Investissement amended the New Equity Derivative Transaction (as defined and described in Amendment No. 27 to the Schedule 13D) through the entry into an amendment agreement (the "Amendment Agreement") relating to the Amended Equity Derivative Transaction Agreements (as defined and described in Amendment No. 27 to the Schedule 13D) with an unaffiliated third party financial institution (the "Bank"). Under the New Equity Derivative Transaction as amended by the Amendment Agreement, Atlas Investissement expects to purchase up to an additional 1,250,000 Common Shares on June 29, 2026. The actual timing and the number of Common Shares to be purchased under such transaction will be determined based on the hedging position of the Bank in accordance with certain parameters of the Amended Equity Derivative Transaction Agreements. The Amendment Agreement also increased the applicable maximum equity notional amount under the Amended Equity Derivative Transaction Agreements, which is intended to help Atlas Investissement purchase the maximum number of Common Shares under the Original Equity Derivative Transaction (as defined and described in Amendment No. 27 to the Schedule 13D) and the New Equity Derivative Transaction as planned. In addition, the Amendment Agreement amended the final maturity date under the Amended Equity Derivative Transaction Agreements to June 29, 2026.

Except as described in this Item 4, the material terms of the Amended Equity Derivative Transaction Agreements governing the Original Equity Derivative Transaction and the New Equity Derivative Transaction remain the same as previously disclosed in Amendment Nos. 26 and 27 to the Schedule 13D.

The foregoing description of the Amendment Agreement is qualified in its entirety by reference to the text of the Amendment Agreement, a copy of which is filed as exhibit to this Amendment No. 28 and incorporated herein by reference.

Separately from the above, on June 23, 2026, Atlas Investissement has irrevocably elected cash settlement for the three European-style call spread option transactions contemplated under each of the respective Letter Agreements on Share Option Transaction (as defined and described in Amendment No. 20 to the Schedule 13D).

**Item 5. Interest in Securities of the Issuer**

**(a)**
See Items 11 and 13 of each of the cover pages.

**(b)**
See Items 7 through 10 of each of the cover pages.

**(c)**
Except as described in Item 4 above, the Reporting Persons did not effect any transactions in Common Shares during the past 60 days.

**Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.**

Item 6 of the Schedule 13D is hereby amended and supplemented as follows:

The information set forth in Item 4 of this Amendment No. 28 is incorporated herein by reference.

### SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Atlas Investissement SAS

**Signature:** /s/ Xavier de Neuville

**Name/Title:** Xavier de Neuville, Managing Director

**Date:** 06/23/2026

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Iliad Holding SAS

**Signature:** /s/ Xavier Niel

**Name/Title:** Xavier Niel, President of Maya SAS, itself President of Iliad Holding SAS

**Date:** 06/23/2026

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Maya SAS

**Signature:** /s/ Xavier Niel

**Name/Title:** Xavier Niel, President

**Date:** 06/23/2026

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Xavier Niel

**Signature:** /s/ Xavier Niel

**Name/Title:** Xavier Niel

**Date:** 06/23/2026

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Jules Niel

**Signature:** /s/ Jules Niel

**Name/Title:** Jules Niel

**Date:** 06/23/2026

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** John Niel

**Signature:** /s/ John Niel

**Name/Title:** John Niel

**Date:** 06/23/2026

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Elisa Niel

**Signature:** /s/ Xavier Niel

**Name/Title:** Xavier Niel, Attorney-in-Fact, for and on behalf of as Parent/Guardian of Elisa Niel

**Date:** 06/23/2026

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** Joseph Niel

**Signature:** /s/ Xavier Niel

**Name/Title:** Xavier Niel, Attorney-in-Fact, for and on behalf of as Parent/Guardian of Joseph Niel

**Date:** 06/23/2026