Director/PDMR Shareholding

Notification of Transactions of Directors, Persons Discharging Managerial Responsibility or Connected Persons

The Administrators of the GlaxoSmithKline Performance Share Plan notified the Company and Mr Phelan on 13 April 2010 of an increase in his interests in Ordinary share ADRs at a price of $38.86 per ADR following the re-investment of the dividend paid to shareholders on 8 April 2010.

This notification relates to a transaction notified in accordance with Disclosure and Transparency Rule 3.1.4R(1)(a).

S M Bicknell

Company Secretary

14 April 2010