X0306 4 2020-05-28 0 0001351288 GW PHARMACEUTICALS PLC GWPH 0001633639 Cline Darren S SOVEREIGN HOUSE, VISION PARK, HISTON CAMBRIDGE X0 CB24 9BZ UNITED KINGDOM 0 1 0 0 U.S. Chief Commercial Officer Ordinary Shares 2020-05-28 4 M 0 7356 0.0012 A 7356 D Ordinary Shares 2020-05-28 4 F 0 1800 10.54 A 5556 D Stock Options 0.0012 2020-05-28 4 M 0 7356 0.00 D 2020-05-28 2020-05-28 Ordinary Shares 7356 0 D Exercise of stock options. Following the exercise, these shares were converted into American Depositary Shares ("ADS") of the Issuer. Each ADS represents twelve ordinary shares of the Issuer. Converted from British Pounds Sterling to U.S. Dollars using currency ratio of 1.00 British Pound Sterling = 1.23 U.S. Dollars as of May 28, 2020. Represented by ADS. The price reported is price per ordinary share converted from price per ADS. Column 5 of Table I of the reporting person's form 4 filed with the SEC on May 30, 2020 includes 29,424 ordinary shares underlying RSU style stock options granted on March 28, 2019 pursuant to the Issuer's Long-Term Incentive Plan, vesting automatically in four equal annual installments beginning on May 28, 2020. These ordinary shares have been excluded from Column 5 of this form 4 and will be reported as each tranche is vested and automatically exercised. The vesting and exercise of the first tranche is reported on this form 4. /s/ Darren S. Cline 2020-05-29