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 attachedⁱⁱ: Summit Therapeutics PLC
Sedol BN40HZ0 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   An acquisition or disposal of financial instruments   An event changing the breakdown of voting rights X Other (please specify)ⁱⁱⁱ:   3. Details of person subject to the notification obligation^iv Name ¹Lansdowne Partners International Limited

²Lansdowne Partners Limited

³Lansdowne Partners (UK) LLP

City and country of registered office (if applicable) London, United Kingdom 4. Full name of shareholder(s) (if different from 3.)^v Name  

HSBC Client Holdings Nominee (UK) Ltd
HSBC Bank Plc Lansdowne Markets

 

(Registered Shareholders)

 

City and country of registered office (if applicable) N/A 5. Date on which the threshold was crossed or reached^vi: 24/12/2019 6. Date on which issuer notified (DD/MM/YYYY): 27/12/2019 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 of issuer^vii Resulting situation on the date on which threshold was crossed or reached 3.92% 2.38% 6.30% 335,873,208 Position of previous notification (if
applicable) 8.21% 4.98% 13.18%  

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 of
shares
ISIN code (if possible) Number of voting rights^ix % of voting rights Direct
(Art 9 of Directive 2004/109/EC) (DTR5.1) Indirect
(Art 10 of Directive 2004/109/EC) (DTR5.2.1) Direct
(Art 9 of Directive 2004/109/EC) (DTR5.1) Indirect
(Art 10 of Directive 2004/109/EC) (DTR5.2.1) GB00BN40HZ01   13,160,170   3.92%                     SUBTOTAL 8. A 13,160,170 3.92%  

 

B 1: Financial Instruments according to Art. 13(1)(a) of Directive 2004/109/EC (DTR5.3.1.1 (a)) Type of financial instrument Expiration
date^x Exercise/
Conversion Period^xi Number of voting rights that may be acquired if the instrument is
exercised/converted. % of voting rights American Depositary Shares (ADS) N/A N/A 7,983,330 2.38%     SUBTOTAL 8. B 1 7,983,330 2.38%  

 

B 2: Financial Instruments with similar economic effect according to Art. 13(1)(b) of Directive 2004/109/EC (DTR5.3.1.1 (b)) Type of financial instrument Expiration
date^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 the
financial instruments are effectively held starting with the ultimate controlling natural person or legal entity^xiv (please add additional rows as necessary) 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 Lansdowne Partners
International Limited 3.92% 2.38% 6.30% Lansdowne Partners
Limited       Lansdowne Partners (UK) LLP 3.92% 2.38% 6.30%   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 This disclosure is being made as a result of the increase in share capital announced by the company and not a as a result of any trading activity by Lansdowne Partners (UK) LLP.