Holding(s) in Company
TR-1: Standard form for notification of major holdings
1. Issuer Details
ISIN
GB00BLDRH360
Issuer Name
OSB GROUP PLC
UK or Non-UK Issuer
UK
2. Reason for Notification
An acquisition or disposal of voting rights
3. Details of person subject to the notification obligation
Name
Dimensional Fund Advisors LP
City of registered office (if applicable)
Austin
Country of registered office (if applicable)
USA
4. Details of the shareholder
| Name | City of registered office | Country of registered office |
| Funds and accounts managed by Dimensional Fund Advisors LP and/or its subsidiary undertakings |
5. Date on which the threshold was crossed or reached
22-Jan-2026
6. Date on which Issuer notified
26-Jan-2026
7. Total positions of person(s) subject to the notification obligation
| . | % of voting rights attached to shares (total of 8.A) | % of voting rights through financial instruments (total of 8.B 1 + 8.B 2) | Total of both in % (8.A + 8.B) | Total number of voting rights held in issuer |
| Resulting situation on the date on which threshold was crossed or reached | 5.003594 | 0.000000 | 5.003594 | 17769925 |
| Position of previous notification (if applicable) |
8. Notified details of the resulting situation on the date on which the threshold was crossed or reached
8A. Voting rights attached to shares
| Class/Type of shares ISIN code(if possible) | Number of direct voting rights (DTR5.1) | Number of indirect voting rights (DTR5.2.1) | % of direct voting rights (DTR5.1) | % of indirect voting rights (DTR5.2.1) |
| GB00BLDRH360 | 17769925 | 5.003594 | ||
| Sub Total 8.A | 17769925 | 5.003594% | ||
8B1. Financial Instruments according to (DTR5.3.1R.(1) (a))
| Type of financial instrument | Expiration date | Exercise/conversion period | Number of voting rights that may be acquired if the instrument is exercised/converted | % of voting rights |
| Sub Total 8.B1 | ||||
8B2. Financial Instruments with similar economic effect according to (DTR5.3.1R.(1) (b))
| Type of financial instrument | Expiration date | Exercise/conversion period | Physical or cash settlement | Number of voting rights | % of voting rights |
| Sub Total 8.B2 | |||||
9. Information in relation to the person subject to the notification obligation
2. Full chain of controlled undertakings through which the voting rights and/or the financial instruments are effectively held starting with the ultimate controlling natural person or legal entities (please add additional rows as necessary)
| Ultimate controlling person | Name of controlled undertaking | % of voting rights if it equals or is higher than the notifiable threshold | % of voting rights through financial instruments if it equals or is higher than the notifiable threshold | Total of both if it equals or is higher than the notifiable threshold |
| Dimensional Holdings Inc. | i) Dimensional Fund Advisors Ltd., (ii) DFA Australia Limited (iii) Dimensional Ireland Limited (iv) Dimensional Fund Advisors Canada ULC (v) Dimensional Fund Advisors Pte. Ltd. and (vi) Dimensional Fund Advisors LP |
10. In case of proxy voting
Name of the proxy holder
The number and % of voting rights held
The date until which the voting rights will be held
11. Additional Information
The ordinary shares are held in segregated accounts and funds (together, the “Accounts”) managed on a discretionary basis by Dimensional Fund Advisors LP ("Dimensional") and its subsidiary undertakings i) Dimensional Fund Advisors Ltd., (ii) DFA Australia Limited (iii) Dimensional Ireland Limited (iv) Dimensional Fund Advisors Canada ULC (v) Dimensional Fund Advisors Pte. Ltd. and (vi) Dimensional Fund Advisors LP.
As at 22 January 2026, Dimensional also had investment management discretion over an additional 48,869 shares where the voting rights are not controlled by Dimensional or its subsidiary undertakings.
Dimensional is controlled by its general partner, Dimensional Holdings Inc.
Dimensional, on behalf of itself and its subsidiary undertakings, expressly disclaims beneficial ownership of the shares held in the Accounts.
12. Date of Completion
26-Jan-2026
13. Place Of Completion
Paris
