Total Voting Rights

GW Pharmaceuticals PLC ("GW Pharmaceuticals")

TOTAL ISSUED SHARE CAPITAL

Cambridge, UK, 30 September 2016: In accordance with the requirements of the FCA's Disclosure and Transparency Rule 5.6.1, GW Pharmaceuticals plc ("GW" or "the Company") (AIM:GWP, NASDAQ:GWPH) confirms that the Company's issued share capital consists of 302,091,675 ordinary shares of 0.1p each in issue, each with equal voting rights. No shares are held in treasury.

The above figure may be used by shareholders as the denominator for the calculations by which they will determine whether they are required to notify their interest, or a change to their interest, in the Company under the FCA's Disclosure and Transparency Rules.

For further information, please contact:

GW Pharmaceuticals PLC +44 (0)1980 557 000

Adam George, Company Secretary

Peel Hunt LLP (Nominated Adviser)

James Steel/Oliver Jackson +44 (0) 20 7418 8900