GlaxoSmithKline : Transfer of Shares out of Treasury

Transfer of Treasury Shares

GlaxoSmithKline plc

(the 'Company')

Notification of Transfer of Shares out of Treasury

On 14 December 2017, the Company transferred 38,600,000ordinary shares of 25 pence each ('Ordinary Shares') that were held by the Company in treasury ('Treasury Shares') to BNY Mellon, the depositary of the Company's American depositary receipts ('ADR') programme, to procure the issuance and transfer of 19,300,000 ADRs of the Company to the GlaxoSmithKline (US) Trust (the 'Trust') to be used to satisfy awards granted under the Company's Deferred Annual Bonus Plan, Performance Share Plan and Share Value Plan. The consideration received from the trustee for the Company procuring the issuance and transfer of the ADRs to the Trust was $35.58 per ADR, representing $17.79 per Ordinary Share, which was funded by a contribution to the Trust from GlaxoSmithKline LLC.

Following the transfer, the Company's issued share capital consisted of 5,372,504,800 Ordinary Shares, of which 414,605,950 were held as Treasury Shares.

Therefore, thetotal number of voting rights in the Company is 4,957,898,850. This figure may be used by shareholders as the denominator for the calculations by which they will determine if they are required to notify their interest in, or a change to their interest in, the Company under the Financial Conduct Authority's Disclosure Guidance and Transparency Rules.

V A Whyte

Company Secretary

15 December 2017