Director/PDMR Shareholding

Notification of Transactions of Directors and Persons Discharging Managerial Responsibility

Vesting of 2007 GlaxoSmithKline Performance Share Plan Awards

The three-year performance period for the GlaxoSmithKline Performance Share Plan (the Performance Share Plan) awards made in 2007, which commenced on 1 January 2007, came to an end on 31 December 2009.

The Remuneration Committee considered the performance achieved in respect of the PSP awards and determined that the:

·; awards granted to Executive Directors and CET members in office in 2007 were dependent on Total Shareholder Return (TSR) performance. The Company ranked at the median of the comparator group and therefore 35% of the awards subject to the TSR measure vested.

·; awards granted in 2007 to senior executives who have since been appointed a CET member, were dependent in part on TSR performance and in part on EPS performance. Half of these awards lapsed as GSK's EPS performance conditions were not met, and 35% of the half of the awards subject to the TSR performance measure vested.

The following Performance Share Plan awards made to the Executive Directors and CET members in office in 2007, vested in part on 23 February 2010 and the balance of the award lapsed, as set out in the table below:

* denotes an Executive Director

Half of the award made in 2007 to senior executives who have since been appointed a CET member lapsed, the other half of the award vested in part (35%), the balance lapsed, on 23 February 2010 as set out in the table below:  

The Company and PDMRs were advised of these transactions on 24 February 2010.

This notification is made in accordance with Disclosure and Transparency Rule 3.1.4R(1)(a).

V Whyte

Deputy Company Secretary

24 February 2010