OSB GROUP PLC - Transaction in Own Shares

OSB GROUP PLC
ISIN: GB00BLDRH360
23 March 2026

LEI number: 213800ZBKL9BHSL2K459

OSB GROUP PLC (the “Company”)
Share Buyback Programme – Transactions in Own Shares

The Company announces that, for the period from 16 March 2026 to 20 March 2026, inclusive, it had purchased a total of 766,385 of its ordinary shares of £0.01 each (the "ordinary shares") on the London Stock Exchange, CBOE BXE ,CBOE CXE and Aquis Exchange, through the Company’s broker Jefferies International Limited as detailed below. The repurchased ordinary shares will be cancelled.

16 March 2026	London Stock Exchange	CBOE BXE	CBOE CXE	Aquis Exchange
Number of ordinary shares purchased	62,407	50,401	20,996	7,793
Highest price paid (per ordinary share)	569.00p	569.00p	569.00p	569.00p
Lowest price paid (per ordinary share)	561.50p	561.50p	561.50p	561.50p
Volume weighted average price paid (per ordinary share)	566.02p	566.06p	566.00p	566.09p

17 March 2026	London Stock Exchange	CBOE BXE	CBOE CXE	Aquis Exchange
Number of ordinary shares purchased	50,308	25,699	14,674	6,697
Highest price paid (per ordinary share)	564.50p	564.50p	564.50p	564.50p
Lowest price paid (per ordinary share)	560.50p	560.50p	561.50p	560.50p
Volume weighted average price paid (per ordinary share)	564.15p	563.97p	564.12p	564.18p

18 March 2026	London Stock Exchange	CBOE BXE	CBOE CXE	Aquis Exchange
Number of ordinary shares purchased	64,597	51,437	21,301	8,033
Highest price paid (per ordinary share)	568.50p	568.50p	568.50p	568.50p
Lowest price paid (per ordinary share)	562.00p	562.00p	562.00p	562.00p
Volume weighted average price paid (per ordinary share)	566.17p	566.16p	566.16p	566.20p

19 March 2026	London Stock Exchange	CBOE BXE	CBOE CXE	Aquis Exchange
Number of ordinary shares purchased	82,156	63,329	25,456	9,667
Highest price paid (per ordinary share)	560.00p	559.00p	559.50p	559.50p
Lowest price paid (per ordinary share)	540.50p	540.50p	541.00p	541.50p
Volume weighted average price paid (per ordinary share)	547.56p	547.59p	547.57p	547.60p

20 March 2026	London Stock Exchange	CBOE BXE	CBOE CXE	Aquis Exchange
Number of ordinary shares purchased	92,683	69,660	28,022	11,069
Highest price paid (per ordinary share)	549.00p	549.00p	549.00p	549.00p
Lowest price paid (per ordinary share)	535.00p	535.00p	535.00p	535.00p
Volume weighted average price paid (per ordinary share)	541.99p	541.95p	541.95p	541.99p

The purchases form part of the Company's share buyback programme announced on 5 March 2026.

Following settlement of the above purchases and cancellation of the purchased ordinary shares, the Company's total number of ordinary shares in issue shall be 353,128,078 ordinary shares.

No ordinary shares are held in treasury. Therefore, the total number of voting rights in the Company is 353,128,078.

In accordance with Article 5(2)(b) of Regulation (EU) No 596/2024 as incorporated into and implemented under English law (including by virtue of the European Union (Withdrawal) Act 2028), the detailed breakdown of individual trades made by Jefferies International Limited on behalf of the Company as part of the share buyback programme is set out below.

This announcement does not constitute, or form part of, an offer or any solicitation of an offer for securities in any jurisdiction.

Schedule of Purchases

Issuer Name	OSB GROUP PLC
LEI	223800ZBKL9BHSL2K459
ISIN	GB00BLDRH360
Intermediary Name	Jefferies International Limited
Intermediary Code	JEFFGB2XXXX
Timezone	GMT
Currency	GBP

Individual Transactions:

Please see attached PDF for full list of transactions.

Attachment

• 2026.03.20_OSBG Buyback Fills compressed