Director/PDMR Shareholding

GW Pharmaceuticals PLC Director/PDMR Shareholding

GW Pharmaceuticals PLC

20 August 2012

GW Pharmaceuticals PLC

GW Pharmaceuticals PLC ("GW Pharmaceuticals" or the "Company")

NOTIFICATION OF INTERESTS OF DIRECTORS AND CONNECTED PERSONS

Porton Down, UK, 20 August 2012: GW Pharmaceuticals (AIM: GWP) hereby provides notification that the Company was today notified that, on 17 August 2012, Dr Geoffrey Guy, a Director and Executive Chairman of the Company, transferred 17,500 0.1 pence ordinary shares of GW Pharmaceuticals plc into his personal pension scheme.

This transaction, representing less than 0.1% of the Company's current issued share capital, was completed when the market price was 70.25 pence per share.

Following this notification Dr Guy's beneficial interest in 17,187,654 GW Pharmaceuticals plc ordinary shares of 0.1 pence each, representing 12.9% of the Company's current issued share capital, remains unchanged.

The total number of shares outstanding in the Company is 133,345,354 ordinary shares of 0.1 pence each.

Enquiries:

GW Pharmaceuticals PLC Tel: +44 (0)1980 557 000

Adam George, Company Secretary

Peel Hunt LLP (Nominated Adviser) Tel: +44 (0)207 418 8900

James Steel/Vijay Barathan