Vianet Grp Regulatory News (VNET)

Vianet Group PLC

James Dickson, Chairman & CEO

Sarah Bentham, CFO

Tel: +44 (0) 1642 358 800

www.vianetplc.com

Cavendish Capital Markets Limited

Stephen Keys / Isaac Hooper

Tel: +44 (0) 20 7220 0500

Investor Enquiries:

Dale Bellis

Tel: +44 (0) 20 7397 1928

www.cavendish.com

NOTIFICATION OF MAJOR HOLDINGS (to be sent to the relevant issuer and to the FCA in Microsoft Word format if possible) i

1a. Identity of the issuer or the underlying issuer of existing shares to which voting rights are attached ii:

Vianet Group PLC

1b. Please indicate if the issuer is a non-UK issuer (please mark with an "X" if appropriate)

Non-UK issuer

2. Reason for the notification (please mark the appropriate box or boxes with an "X")

An acquisition or disposal of voting rights

X

An acquisition or disposal of financial instruments

An event changing the breakdown of voting rights

Other (please specify) iii:

3. Details of person subject to the notification obligation iv

Name

Lord Lee of Trafford

City and country of registered office (if applicable)

London, UK

4. Full name of shareholder(s) (if different from 3.) v

Name

City and country of registered office (if applicable)

London, UK

5. Date on which the threshold was crossed or reached vi:

20/11/2025

6. Date on which issuer notified (DD/MM/YYYY):

20/11/2025

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 (8.A + 8.B) vii

Resulting situation on the date on which threshold was crossed or reached

4.68%

4.68%

1,331,000

Position of previous notification (if

applicable)

3.98%

3.98%

8. Notified details of the resulting situation on the date on which the threshold was crossed or reached viii

A: Voting rights attached to shares

Class/type ofshares

ISIN code (if possible)

Number of voting rights ix

% of voting rights

Direct

(DTR5.1)

Indirect

 (DTR5.2.1)

Direct

(DTR5.1)

Indirect

(DTR5.2.1)

GB00B13YVN56

1,331,000

4.68%

SUBTOTAL 8. A

1,331,000

4.68%

B 1: Financial Instruments according to DTR5.3.1R (1) (a)

Type of financial instrument

Expirationdate x

Exercise/Conversion Period xi

Number of voting rights that may be acquired if the instrument is

exercised/converted.

% of voting rights

SUBTOTAL 8. B 1

B 2: Financial Instruments with similar economic effect according to DTR5.3.1R (1) (b)

Type of financial instrument

Expirationdate x

Exercise/Conversion Period xi

Physical or cash

Settlement xii

Number of voting rights

% of voting rights

SUBTOTAL 8.B.2

9. Information in relation to the person subject to the notification obligation (please mark the

applicable box with an "X")

Person subject to the notification obligation is not controlled by any natural person or legal entity and does not control any other undertaking(s) holding directly or indirectly an interest in the (underlying) issuer xiii

Full chain of controlled undertakings through which the voting rights and/or thefinancial instruments are effectively held starting with the ultimate controlling natural person or legal entity (please add additional rows as necessary) xiv

X

Name xv

% 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

Lord Lee of Trafford

4.68%

4.68%

10. In case of proxy voting, please identify:

Name of the proxy holder

N/A

The number and % of voting rights held

N/A

The date until which the voting rights will be held

N/A

11. Additional information xvi

Place of completion

London

Date of completion

20/11/2025