Appointment of Non-Executive Director

DIPLOMA PLC

12 CHARTERHOUSE SQUARE, LONDON EC1M 6AX

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FOR IMMEDIATE RELEASE

14 November 2012

DIPLOMA PLC

APPOINTMENT OF NON-EXECUTIVE DIRECTOR

Diploma PLC, the international group of specialised businesses supplying technical products and services, today announces the appointment of Marie-Louise Clayton as a Non-Executive Director of Diploma PLC.

Marie-Louise, who is a qualified accountant, will also be a member of the Audit Committee in place of John Rennocks, Chairman of the Company, who steps down as a member of the Audit Committee.

Marie-Louise is currently a Non-Executive Director of Zotefoams PLC and was a Non-Executive Director and Chairman of the Audit Committee of Forth Ports PLC from 2009 until its sale in 2011. Marie-Louise was previously Group Finance Director of Venture Production PLC and has held senior positions in Alstom (formerly, Alsthom GEC).

Commenting on the appointment, John Rennocks, Chairman of Diploma PLC said:

"I am delighted that Marie-Louise will be joining our Board and look forward to the experience and financial skills that Marie-Louise will bring to Diploma."

There are no disclosures required under paragraph 9.6.13(2)-(6) of the Listing Rules of the UK Listing Authority.

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