Holding in Company

Porvair PLC
19 March 2007



Holding in Company

1. Identity of the issuer or the underlying issuer of existing shares to which
voting rights are attached:

Porvair plc

2. Reason for the notification (please tick the appropriate box or boxes):

An acquisition or disposal of voting rights:

(  )

An acquisition or disposal of financial instruments which may result in the
acquisition of shares already issued to which voting rights are attached:

(  )

An event changing the breakdown of voting rights:

(  )

Other (please specify):

Confirmation of current position using this standard form as required by EUTD
regulations

( X )

3. Full name of person(s) subject to the notification obligation:

Prudential plc group of companies

4. Full name of shareholder(s) (if different from 3.):

See attached schedule

5. Date of the transaction (and date on which the threshold is crossed or
reached if different):

14/03/2007

6. Date on which issuer notified:

15/03/2007

7. Threshold(s) that is/are crossed or reached:

14%

8. Notified details:

A: Voting rights attached to shares

Class/type of shares            Situation previous to the triggering transaction
                                 
                                  Number of Shares       Number of Voting Rights
GB0006963689                            6,080,987                      6,080,987


Resulting situation after the triggering transaction

Number of shares             Number of voting rights          % of voting rights
Direct                       Direct         Indirect       Direct       Indirect
6,080,987                 6,080,987                        14.98%


B: Financial Instruments

Resulting situation after the triggering transaction
Type of     Expiration Exercise /     Number of voting rights that may   % of
financial   date       conversion     be acquired if the instrument is   voting
instrument             period / date  exercised / converted              rights
n/a         n/a        n/a            n/a                                n/a


Total (A+B):

Number of voting rights               % of voting rights
              6,080,987                           14.98%


9. Chain of controlled undertakings through which the voting rights and/or the
financial instruments are effectively held, if applicable:

Prudential plc (parent Company)
M&G Group Limited (wholly owned subsidiary of Prudential plc)
M&G Limited (wholly owned subsidiary of M&G Group Limited)
M&G Investment Management Limited (wholly owned subsidiary of M&G Limited)
M&G Securities Limited (wholly owned subsidiary of M&G Limited)

Proxy Voting:

10. Name of the proxy holder:

n/a

11. Number of voting rights proxy holder will cease to hold:

n/a

12. Date on which proxy holder will cease to hold voting rights:

n/a

13. Additional information:

None

14. Contact name:

Chris Tyler
Group Finance Director and Company Secretary
Porvair plc

15. Contact telephone number:

01553 765 500


--------------------


Schedule of notifiable position

                  Registered Holder        Holding        %

Prudential plc                           6,080,987    14.98   Total notifiable
                                                              interest
                  Nortrust Nominee Ltd   5,320,632
                  A/C MKK01
                  PRUCLT HSBC GIS NOM      760,355
                  (UK) PPL AC

M&G Group Limited                        6,080,987    14.98
                  Nortrust Nominee Ltd   5,320,632
                  A/C MKK01
                  PRUCLT HSBC GIS NOM      760,355
                  (UK) PPL AC

M&G Investment
Management                               6,080,987    14.98
Limited
                  Nortrust Nominee Ltd   5,320,632
                  A/C MKK01
                  PRUCLT HSBC GIS NOM      760,355
                  (UK) PPL AC

M&G Limited                              6,080,987    14.98
                  Nortrust Nominee Ltd   5,320,632
                  A/C MKK01
                  PRUCLT HSBC GIS NOM      760,355
                  (UK) PPL AC

M&G Securities                           5,320,632    13.11
Limited
                  Nortrust Nominee Ltd   5,320,632
                  A/C MKK01




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