GlaxoSmithKline plc

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

In accordance with DTR 3.1.4 R(1)(c) GlaxoSmithKline plc ('GSK') was advised on 23 June 2015 of the following increase in the notional allocation of GSK American Depositary Shares ('ADSs') on 22 June 2015, at a price of $43.45 per ADS, following the revaluation of the cash element of the notional investment held within the GSK 401K plan:

V A Whyte

Company Secretary

24 June 2015