Transaction in own shares

OSB GROUP PLC                                        
ISIN: GB00BLDRH360
26 September 2025

LEI number: 213800ZBKL9BHSL2K459

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

The Company announces that on 25 September 2025 it had purchased a total of 26,530 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	26,530	-	-
Highest price paid (per ordinary share)	553.50p	-	-
Lowest price paid (per ordinary share)	549.00p	-	-
Volume weighted average price paid (per ordinary share)	551.88p	-	-

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 360,269,199 ordinary shares.

No ordinary shares are held in treasury. Therefore, the total number of voting rights in the Company is 360,269,199.

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
25-09-2025	16:28:12	GBp	148	551.00	XLON	xeaNiwgmttb
25-09-2025	16:28:12	GBp	306	551.00	XLON	xeaNiwgmtte
25-09-2025	16:27:15	GBp	35	551.00	XLON	xeaNiwgmqNO
25-09-2025	16:27:12	GBp	353	551.00	XLON	xeaNiwgmqGS
25-09-2025	16:27:12	GBp	75	551.50	XLON	xeaNiwgmqJa
25-09-2025	16:27:12	GBp	190	551.50	XLON	xeaNiwgmqJY
25-09-2025	16:27:07	GBp	210	551.50	XLON	xeaNiwgmqQF
25-09-2025	16:27:05	GBp	205	551.50	XLON	xeaNiwgmrWf
25-09-2025	16:25:42	GBp	826	551.50	XLON	xeaNiwgmp6H
25-09-2025	16:25:42	GBp	734	551.50	XLON	xeaNiwgmp6J
25-09-2025	16:25:41	GBp	206	552.00	XLON	xeaNiwgmp1K
25-09-2025	16:25:33	GBp	129	552.00	XLON	xeaNiwgmpHn
25-09-2025	16:25:33	GBp	97	552.00	XLON	xeaNiwgmpHp
25-09-2025	16:25:25	GBp	215	552.00	XLON	xeaNiwgmmb@
25-09-2025	16:25:17	GBp	215	552.00	XLON	xeaNiwgmmkX
25-09-2025	16:25:09	GBp	230	552.00	XLON	xeaNiwgmmzf
25-09-2025	16:25:03	GBp	1	552.00	XLON	xeaNiwgmm0S
25-09-2025	16:25:03	GBp	152	552.00	XLON	xeaNiwgmm0U
25-09-2025	16:24:55	GBp	214	552.00	XLON	xeaNiwgmmIA
25-09-2025	16:24:47	GBp	207	552.00	XLON	xeaNiwgmnag
25-09-2025	16:24:40	GBp	352	552.00	XLON	xeaNiwgmnky
25-09-2025	16:24:39	GBp	10	552.00	XLON	xeaNiwgmnh3
25-09-2025	16:24:38	GBp	252	552.00	XLON	xeaNiwgmnhT
25-09-2025	16:24:38	GBp	108	552.00	XLON	xeaNiwgmngy
25-09-2025	16:24:38	GBp	31	552.00	XLON	xeaNiwgmng@
25-09-2025	16:24:38	GBp	15	552.00	XLON	xeaNiwgmng0
25-09-2025	16:24:38	GBp	105	552.00	XLON	xeaNiwgmng2
25-09-2025	16:24:38	GBp	427	552.00	XLON	xeaNiwgmng4
25-09-2025	16:24:38	GBp	475	552.00	XLON	xeaNiwgmng6
25-09-2025	16:20:48	GBp	40	551.50	XLON	xeaNiwgmxaN
25-09-2025	16:20:48	GBp	252	551.50	XLON	xeaNiwgmxaP
25-09-2025	16:20:34	GBp	242	551.50	XLON	xeaNiwgmxyj
25-09-2025	16:20:29	GBp	320	552.00	XLON	xeaNiwgmx1Y
25-09-2025	16:20:14	GBp	1,157	551.50	XLON	xeaNiwgmxVH
25-09-2025	16:20:14	GBp	26	551.50	XLON	xeaNiwgmxVJ
25-09-2025	16:20:14	GBp	302	551.50	XLON	xeaNiwgmxVQ
25-09-2025	16:17:43	GBp	112	551.50	XLON	xeaNiwgmdzp
25-09-2025	16:17:43	GBp	258	551.50	XLON	xeaNiwgmdzq
25-09-2025	16:17:43	GBp	616	552.00	XLON	xeaNiwgmdzJ
25-09-2025	16:17:43	GBp	1,405	552.50	XLON	xeaNiwgmdzL
25-09-2025	16:17:41	GBp	1,131	553.50	XLON	xeaNiwgmd@p
25-09-2025	16:17:41	GBp	413	553.50	XLON	xeaNiwgmd@r
25-09-2025	16:17:41	GBp	263	553.50	XLON	xeaNiwgmd@t
25-09-2025	16:17:41	GBp	69	553.50	XLON	xeaNiwgmd@v
25-09-2025	16:17:41	GBp	492	553.50	XLON	xeaNiwgmd@x
25-09-2025	16:17:41	GBp	10	553.50	XLON	xeaNiwgmd@z
25-09-2025	16:17:41	GBp	40	553.50	XLON	xeaNiwgmd@$
25-09-2025	16:17:41	GBp	8	553.50	XLON	xeaNiwgmd@3
25-09-2025	16:17:41	GBp	1,212	553.00	XLON	xeaNiwgmd@B
25-09-2025	14:57:29	GBp	241	552.50	XLON	xeaNiwgowxq
25-09-2025	14:57:29	GBp	254	552.50	XLON	xeaNiwgowxs
25-09-2025	14:57:29	GBp	8	552.00	XLON	xeaNiwgowxF
25-09-2025	14:57:28	GBp	8	552.00	XLON	xeaNiwgow5l
25-09-2025	14:57:28	GBp	8	552.00	XLON	xeaNiwgow5t
25-09-2025	14:57:27	GBp	8	552.00	XLON	xeaNiwgow4Y
25-09-2025	14:57:27	GBp	8	552.00	XLON	xeaNiwgow4e
25-09-2025	14:57:27	GBp	20	552.00	XLON	xeaNiwgow4t
25-09-2025	14:57:27	GBp	8	552.00	XLON	xeaNiwgow4v
25-09-2025	14:48:01	GBp	240	551.50	XLON	xeaNiwgojHo
25-09-2025	14:48:01	GBp	967	552.00	XLON	xeaNiwgojGl
25-09-2025	14:47:41	GBp	437	552.50	XLON	xeaNiwgoggZ
25-09-2025	14:47:35	GBp	3	552.50	XLON	xeaNiwgogx@
25-09-2025	14:47:35	GBp	3	552.50	XLON	xeaNiwgogx0
25-09-2025	14:47:35	GBp	1,681	552.50	XLON	xeaNiwgogx2
25-09-2025	14:47:35	GBp	9	552.50	XLON	xeaNiwgogx4
25-09-2025	14:47:35	GBp	1	552.50	XLON	xeaNiwgogx8
25-09-2025	14:47:35	GBp	3	552.50	XLON	xeaNiwgogxA
25-09-2025	14:47:35	GBp	20	552.50	XLON	xeaNiwgogxC
25-09-2025	14:47:35	GBp	733	552.50	XLON	xeaNiwgogxy
25-09-2025	14:45:50	GBp	244	552.50	XLON	xeaNiwgof6N
25-09-2025	14:14:16	GBp	295	551.00	XLON	xeaNiwgp@Da
25-09-2025	14:14:16	GBp	14	551.00	XLON	xeaNiwgp@De
25-09-2025	14:14:16	GBp	13	551.00	XLON	xeaNiwgp@Dg
25-09-2025	13:58:12	GBp	776	550.50	XLON	xeaNiwgpiKh
25-09-2025	13:51:51	GBp	445	549.00	XLON	xeaNiwgpKfs
25-09-2025	13:49:49	GBp	423	549.50	XLON	xeaNiwgpIxM
25-09-2025	13:49:32	GBp	93	549.50	XLON	xeaNiwgpIAQ
25-09-2025	13:49:30	GBp	655	550.00	XLON	xeaNiwgpIKp
25-09-2025	13:33:08	GBp	249	550.00	XLON	xeaNiwgpFyq
25-09-2025	13:32:54	GBp	357	550.50	XLON	xeaNiwgpCbY
25-09-2025	13:32:54	GBp	691	550.50	XLON	xeaNiwgpCbI
25-09-2025	13:18:10	GBp	460	551.00	XLON	xeaNiwgi$FM
25-09-2025	13:18:10	GBp	26	551.00	XLON	xeaNiwgi$FO
25-09-2025	13:12:03	GBp	528	551.50	XLON	xeaNiwgivK3
25-09-2025	12:32:10	GBp	227	552.50	XLON	xeaNiwgiFoN
25-09-2025	12:21:07	GBp	300	552.50	XLON	xeaNiwgjrGt
25-09-2025	12:20:46	GBp	654	552.50	XLON	xeaNiwgjo7h
25-09-2025	12:14:38	GBp	529	552.50	XLON	xeaNiwgjy0E