Holding(s) in Company

Porvair PLC
26 July 2005


LETTER TO:  RNS

             Section 198 Companies Act 1985 - notifiable interests

We were advised today that:

•  Schroder Investment Management Limited has an interest in 8,508,035 shares in 
   Porvair plc, which are held in portfolios managed by them on a discretionary 
   basis for clients under investment management agreements.  
   This interest represents 23.12% of the Company's issued share capital.

•  The Universities Superannuation Scheme Limited has reduced its holding to 
   1,000,000 shares in Porvair plc, representing 2.72% of the Company's issued 
   share capital.

From:  C P Tyler (Company Secretary)

                      This information is provided by RNS
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