Block Listing Six Monthly Return

Name of applicant:

HORIZON DISCOVERY GROUP PLC

Names of schemes:

a) Horizon Discovery Limited Enterprise Management Incentive Share Option Scheme

b) Horizon Discovery Group plc Long Term Incentive Plan

c) Horizon Discovery 2014 Sharesave Scheme

d) Horizon Discovery Group plc US Employee Stock Purchase Plan

Period of return:

From:

26 July 2017

To:

26 January 2018

Number of securities originally admitted and date of admission:

3,000,000 ordinary shares of 1p each

26 July 2017

Balance of unallotted securities under schemes from previous return:

a) 1,398,000 ordinary shares of 1p each

b) 1,392,000 ordinary shares of 1p each

c) 110,000 ordinary shares of 1p each

d) 100,000 ordinary shares of 1p each

Plus: The amount by which the block schemes has been increased since the date of the last return (if any increase has been applied for):

a) 0

b) 0

c) 0

d) 0

Less: Number of securities issued/allotted under schemes during period:

a) 220,656

b) 85,360

c) 85,329

d) 34,145

Equals: Balance under schemes not yet issued/allotted at end of period:

a) 1,177,344

b) 1,306,640

c) 24,671

d) 65,855

Name of contact:

Richard Vellacott, Chief Financial Officer and Deputy CEO

Telephone number of contact:

Tel. +44 (0) 122 320 4788