Groupe Bruxelles Lambert SA

Transaction in Own Shares • Nov 10, 2025

Delivering meaningful growth

Transactions on GBL Shares

Disclosure of transaction on GBL shares from November 3, 2025, until November 7, 2025 (included) Implementation of the authorization of the Extraordinary General Shareholders' Meeting of May 2, 2025

Purchases

GBL, directly and through its subsidiaries, acquired during the period from November 3, 2025 until November 7, 2025 included, as part of:

• The share buyback program: 0 GBL share
• The share buyback program by an independent financial institution on the basis of a discretionary mandate (until November 7, 2025) in the central order book of a regulated market or MTF: 95,287 GBL shares

Trade date	Number of shares	Average price (EUR)	Lowest price (EUR)	Highest price (EUR)	Amount (EUR)	Market (MIC Code)
11/03/2025	6,182	76.58	75.95	76.80	473,433	CEUX
11/03/2025	1,464	76.56	76.30	76.80	112,088	TQEX
11/03/2025	11,653	76.60	76.25	76.80	892,606	XBRU
11/04/2025	3,562	76.17	75.60	76.45	271,320	CEUX
11/04/2025	1,290	75.75	75.55	76.20	97,718	TQEX
11/04/2025	7,020	76.20	75.50	76.50	534,952	XBRU
11/05/2025	3,555	76.19	75.70	76.50	270,860	CEUX
11/05/2025	1,275	75.84	75.75	76.20	96,701	TQEX
11/05/2025	6,325	76.27	75.80	76.65	482,394	XBRU
11/06/2025	5,171	76.31	76.10	76.70	394,610	CEUX
11/06/2025	1,290	76.51	76.30	76.80	98,695	TQEX
11/06/2025	13,336	76.30	76.00	76.90	1,017,477	XBRU
11/07/2025	10,333	72.09	71.40	73.25	744,924	CEUX
11/07/2025	1,861	72.37	71.40	73.05	134,681	TQEX
11/07/2025	20,970	72.04	71.50	73.85	1,510,641	XBRU
Total	95,287	74.86			7,133,099

• The liquidity agreement: 0 GBL share

Sales

GBL, directly and through its subsidiaries, sold during the period from November 3, 2025 until November 7, 2025 included, as part of:

• The liquidity agreement: 0 GBL share

As of November 7, 2025, GBL holds directly and through its subsidiaries 11,726,909 GBL shares representing 8.8% of the issued capital and holds no shares under the liquidity agreement. On that date, 16.1% of the eighth share buyback program is executed¹ .

Following GBL's decision to use the safe harbour² regime for the on-the-market share buybacks in the context of a EUR 598.9 million envelope, the liquidity contract with an independent financial institution has been suspended for an indefinite period.

For more information, please contact:

Tel: +32 2 289 17 72 Tel: +32 2 289 17 64

Xavier Likin Alison Donohoe

Chief Financial Officer Head of Investor Relations xlikin@gbl.com adonohoe@gbl.com

About Groupe Bruxelles Lambert

Groupe Bruxelles Lambert ("GBL") is an established investment holding company, with seventy years of stock exchange listing and a net asset value of €14.0bn at the end of September 2025. As a leading and active investor in Europe, GBL focuses on long-term value creation with the support of a stable family shareholder base.

GBL is focused on delivering meaningful growth by providing attractive returns to its shareholders through a combination of growth in its net asset value per share, a sustainable dividend and share buybacks.

GBL is listed on Euronext Brussels (Ticker: GBLB BB; ISIN code: BE0003797140) and is included in the BEL20 index.

¹ cf. http://www.gbl.com/en/transactions-gbl-shares

² Provided for in Regulation (EU) No. 596/2014 of 16 April 2014 on market abuse and Delegated Regulation (EU) No. 2016/1052 of 8 March 2016 with regard to regulatory technical standards for the terms of buyback programs and stabilization measures