Director/PDMR Shareholding

GlaxoSmithKline PLC
23 March 2007







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



I give below details of changes in the interests of Directors, Persons
Discharging Managerial Responsibility or Connected Persons in the Ordinary
Shares and Ordinary Share ADRs ("ADRs") of GlaxoSmithKline plc ("the Company").


   22 March 2007                 Abacus (GSK) Trustees Limited, as trustee of the
                                 GlaxoSmithKline Employee Trust, ("the GSK Trust"), transferred
                                 4,736 Ordinary Shares in the Company to participants in the
                                 SmithKline Beecham Employee Share Option Plan 1991.


                                 Abacus Corporate Trustees Limited, as trustee of the
                                 GlaxoSmithKline (US) Trust ("the GSK US Trust") transferred 25
                                 ADRs of GlaxoSmithKline plc to participants in the
                                 GlaxoSmithKline Performance Share Plan.



The Company was advised of these transactions on 22 March 2007.


   22 March 2007                 The GSK US Trust sold 2,043 ADRs of GlaxoSmithKline plc at a
                                 price of $55.64 per ADR on behalf of participants in the
                                 GlaxoSmithKline Performance Share Plan.


                                 The GSK US Trust transferred 4,422 ADRs of GlaxoSmithKline plc
                                 to participants in the GlaxoSmithKline Performance Share Plan.



The Company was advised of these transactions on 23 March 2007.



The GSK Trust is a discretionary trust of which all employees or former
employees of GlaxoSmithKline plc and its subsidiaries are potential
beneficiaries. Three of the Company's directors, Dr J-P Garnier, Dr M M Slaoui
and Mr J S Heslop are therefore interested in the shares held in the GSK Trust
from time to time in the same way as other employees or former employees of
GlaxoSmithKline plc and its subsidiaries.



The GSK US Trust is a grantor trust of which all employees or former employees
of SmithKline Beecham Corporation and its subsidiaries are potential
beneficiaries. Two of the Company's directors, Dr J-P Garnier and Dr M M Slaoui
are therefore interested in the shares held in the GSK US Trust from time to
time in the same way as other employees or former employees of SmithKline
Beecham Corporation and its subsidiaries.



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





S M Bicknell

Company Secretary



23 March 2007


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