Holding(s) in Company

21st November 2024

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

System1 Group plc

GB00B1GVQH21

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

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

Octopus Investments Limited

City and country of registered office (if applicable)

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

Name

City and country of registered office (if applicable)

London, England

Name

City and country of registered office (if applicable)

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

20/11/2024

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

21/11/2024

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

4.330000

0.000000

4.330000

550000

Position of previous notification (if

applicable)

3.190000

0.000000

3.190000

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)

GB00B1GVQH21

0

550000

0.000000

4.330000

SUBTOTAL 8. A

550000

4.330000%

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

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

Octopus Capital Limited

Octopus Investments Limited

4.330000

4.330000%

10. In case of proxy voting, please identify:

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 xvi

Place of completion

London

Date of completion

21/11/2024