Director/PDMR Shareholding

Immunodiagnostic Systems Holdings PLC

("IDS" or the "Company")

Director/PDMR Shareholding

Immunodiagnostic Systems Holdings PLC (AIM: IDH), a leading producer of diagnostic testing kits and automated systems for the clinical and research markets, announces that it was informed on 1 August 2012 that Forum Venture Capital GmbH ("FVC"), bought a total of 300,000 ordinary shares of 2p each ("Ordinary Shares") in the Company on 31 July 2012 at a purchase price of 245 pence. Dr Burkhard Wittek is a Director of both the Company and of FVC.

 Following this transaction FVC has a beneficial interest in 6,936,188 shares in the Company. Based on 28,336,915 Ordinary Shares of 2p each in issue FVC's resultant holding represents 24.48% of the Company's issued share capital. The aggregate beneficial holding of Dr Burkhard Wittek in the Company is now 7,969,931 shares representing 28.13% of the Company's issued share capital. The Company does not hold any Ordinary Shares in Treasury.

For further information:

Immunodiagnostic Systems Holdings PLC Tel: +44 (0)191 519 0660

Patrick Dahlen, Chief Executive Officer

Gerard Murray, Finance Director

Peel Hunt LLP Tel: +44 (0)207 418 8900

James Steel

Dr Vijay Barathan

FTI Consulting Tel: +44 (0)207 831 3113

Simon Conway

Mo Noonan