MBB SE: Disclosure pursuant to Art. 5 Sec. 1 lit. b) and Sec. 3 of the Regulation (EU) No 596/2014 (MAR) in conjunction with Art. 2 Sec. 2 and Sec. 3 of the Commission Delegated Regulation (EU) No 201

MBB SE/ Share buyback

MBB SE: Disclosure pursuant to Art. 5 Sec. 1 lit. b) and Sec. 3 of the Regulation (EU) No 596/2014 (MAR) in conjunction with Art. 2 Sec. 2 and Sec. 3 of the Commission Delegated Regulation (EU) No 201

18.05.2026 / 18:06 CET/CEST

Dissemination of a Post-admission Duties announcement transmitted by EQS News – a service of EQS Group.

The issuer is solely responsible for the content of this announcement.

Share buyback: Disclosure pursuant to Art. 5 Sec. 1 lit. b) and Sec. 3 of the Regulation (EU) No 596/2014 (MAR) in conjunction with Art. 2 Sec. 2 and Sec. 3 of the Commission Delegated Regulation (EU) No 2016/1052

Purchase of own shares – 23rd interim notification

In the period from 11 May 2026 up to and including 15 May 2026, a total of 5,767 shares were purchased under the share buyback program 2025. The initiation of the share buyback program was communicated by way of an announcement dated 09 December 2025 pursuant to Article 5 of Regulation (EU) No. 596/2014 and Article 2 (1) of Commission Delegated Regulation (EU) 2016/1052.

The total number of shares purchased in the period from 11 May 2026 up to and including 15 May 2026 per day, exchange, average price and volume in euros are as follows:

1 Excl. acquisition costs

The total number of shares bought back under the share buyback program 2025 in the period up to and including 15 May 2026 amounts to 121,621 shares.

The share buyback has been executed by mwb fairtrade Wertpapierhandelsbank AG.

Information about individual transactions and daily trading volumes pursuant to Article 5 of Regulation (EU) No. 596/2014 and Commission Delegated Regulation (EU) 2016/1052 has been published on the internet at the following link: https://www.mbb.com/en/ir/shares/buyback.html

Berlin, 18 May 2026

MBB SE

MBB SE

Kurfürstendamm 188

10707 Berlin

Tel +49 30 844 15 330

ir@mbb.com

www.mbb.com

Chairman of the Board of Directors and Executive Management

Dr Christof Nesemeier

Executive Management

Torben Teichler

Register court

Berlin-Charlottenburg Local Court, registration number: HRB 165458

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