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

20 February 2012

DIPLOMA PLC

DIRECTORS' INTERESTS IN SHARES

The Company has been notified that on 17 February 2012, Mr I Henderson, a Director of the Company, sold 35,000 ordinary shares of 5p each in the Company ("Ordinary Shares") at 391 pence per share. Following this transaction Mr I Henderson is interested in a total of 452,433 Ordinary Shares representing approximately 0.4% of the Company's issued share capital.

The Company has also been notified that on 17 February 2012, Mr BM Thompson, a Director of the Company, transferred 62,500 ordinary shares of 5p each in the Company ("Ordinary Shares") for nil consideration to a charitable foundation of which Mr Thompson is a trustee. These shares were subsequently sold at 391 pence per share. Following this transaction Mr BM Thompson is interested in a total of 1,120,569 Ordinary Shares representing approximately 1.0% of the Company's issued share capital.

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