OSB GROUP PLC - Transaction in Own Shares

OSB GROUP PLC                                        
ISIN: GB00BLDRH360
09 December 2025

LEI number: 213800ZBKL9BHSL2K459

OSB GROUP PLC (the “Company”)
Transaction in Own Shares

The Company announces that on 08 December 2025 it had purchased a total of 2,873 of its ordinary shares of £0.01 each (the "ordinary shares") on the London Stock Exchange, CBOE BXE and CBOE CXE, through the Company's broker Citigroup Global Markets Limited as detailed below. The repurchased ordinary shares will be cancelled.

	London Stock Exchange	CBOE BXE	CBOE CXE
Number of ordinary shares purchased	2,873	-	-
Highest price paid (per ordinary share)	568.00p	-	-
Lowest price paid (per ordinary share)	566.50p	-	-
Volume weighted average price paid (per ordinary share)	567.70p	-	-

The purchases form part of the Company’s share buyback programme announced on 13 March 2025.

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 356,783,830 ordinary shares.

No ordinary shares are held in treasury. Therefore, the total number of voting rights in the Company is 356,783,830.

In accordance with Article 5(1)(b) of Regulation (EU) No 596/2014 as incorporated into and implemented under English law (including by virtue of the European Union (Withdrawal) Act 2018), the detailed breakdown of individual trades made by Citigroup Global Markets 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 – Individual Transactions

Issuer Name	OSB GROUP PLC
LEI	213800ZBKL9BHSL2K459
ISIN	GB00BLDRH360
Intermediary Name	Citigroup Global Markets Limited
Intermediary Code	SBILGB2L
Timezone	GMT+1
Currency	GBP

Transaction Date	Trade Time	Currency	Volume	Price	Trading Venue	Transaction ID
08-12-2025	09:42:28	GBp	5	568.00	XLON	xeaNdIRO7$j
08-12-2025	09:42:28	GBp	186	568.00	XLON	xeaNdIRO7$l
08-12-2025	09:16:55	GBp	277	567.50	XLON	xeaNdIRO3@8
08-12-2025	09:16:55	GBp	619	568.00	XLON	xeaNdIRO3@E
08-12-2025	09:09:02	GBp	42	568.00	XLON	xeaNdIRO0LM
08-12-2025	08:57:42	GBp	386	566.50	XLON	xeaNdIROELb
08-12-2025	08:54:17	GBp	272	567.50	XLON	xeaNdIROFzF
08-12-2025	08:54:17	GBp	139	568.00	XLON	xeaNdIROFzH
08-12-2025	08:54:17	GBp	251	568.00	XLON	xeaNdIROFzJ
08-12-2025	08:37:18	GBp	696	568.00	XLON	xeaNdIROABb