Director/PDMR Shareholding

DIPLOMA PLC

12 CHARTERHOUSE SQUARE, LONDON EC1M 6AX

TELEPHONE: +44 (0)20 7549 5700

FACSIMILE: +44 (0)20 7549 5715

FOR IMMEDIATE RELEASE

10 August 2012

DIPLOMA PLC

DIRECTORS' INTERESTS IN SHARES

Diploma PLC has been notified that on 9 August 2012, Mr BM Thompson, Chief Executive Officer of the Company, has disposed of 75,000 ordinary shares of 5p each in the Company ("Ordinary Shares") at 426 pence per share and has acquired, through a Self Invested Pension Plan, 75,000 Ordinary Shares at 426 pence per share. Mr Thompson has also disposed of 6,250 Ordinary Shares at 422 pence per share and has acquired, through a personal savings vehicle, 6,250 Ordinary Shares at 422 pence per share. His beneficial interest in the shares of the Company remains unchanged at 1,120,569 Ordinary Shares, representing approximately 1.0% of the Company's issued share capital.

The Company has also been notified that on 9 August 2012, Mr I Henderson, a Director of the Company, has disposed of 11,000 Ordinary Shares at 423 pence per share and has acquired, through a personal savings vehicle, 11,000 Ordinary Shares at 423 pence per share. His beneficial interest in the shares of the Company remains unchanged at 452,433 Ordinary Shares, representing approximately 0.4% of the Company's issued share capital.

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