Holding(s) in Company

OMG PLC
22 March 2007


TR-1(i): NOTIFICATION OF MAJOR INTERESTS IN SHARES


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


OMG PLC


2. Reason for the notification (please state Yes/No): ( )

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): Final deadline Re: DTR 5


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

Herald Investment Management Limited

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





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

N/A

6. Date on which issuer notified:


20 March 2007


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

9%


8. Notified details:



A: Voting rights attached to shares

Class/type of shares if possible      Situation previous to the Triggering transaction(vi)
using the ISIN CODE                                         
                                      Number of shares  Number of voting Rights (viii)
GB0030312788                          5,876,750 (9.78%)               5,876,750 (9.78%)


Resulting situation after the triggering transaction (vii)
Class/type of shares if               Number of shares         Number of voting rights (ix)    % of voting rights
possible using the ISIN
CODE
                                         Direct               Direct (x)      Indirect (xi)     Direct   Indirect
GB0030312788                                                                  5,876,750         0           9.78%


B: Financial Instruments

Resulting situation after the triggering transaction (xii)
Type of        Expiration Date     Exercise/Conversion      Number of voting rights     % of voting rights
financial      (xiii)                Period/Date (xiv)        that may be acquired if
instrument                                                   the instrument is
                                                             exercised/ converted.

N/A                      N/A                      N/A                       N/A                    N/A


Total (A+B)

    Number of voting rights     % of voting rights
                  5,876,750                  9.78%


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


Herald Investment Management Limited, a discretionary investment manager, is the
parent undertaking of an investment management business.

+--------------------------------------------------------------+-------------------+--------------------+
|Legal Vehicle                                                 |      Voting Rights      Percentage held     
+--------------------------------------------------------------+-------------------+--------------------+
|                                                              |                   |                    |
+--------------------------------------------------------------+-------------------+--------------------+
|Herald Investment Trust (in the name of Bank of New York (OCS |          5,876,750|               9.78%|
|Nominees Limited)                                             |                   |                    |
+--------------------------------------------------------------+-------------------+--------------------+
|Total for Funds under the management of Herald Investment     |          5,876,750|               9.78%|
|Management 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:



14. Contact name:


Andrew Miller


15. Contact telephone number:


[phone]


Annex to Notification Of Major Interests In Shares (xvi)


A: Identity of the person or legal entity subject to the notification obligation


Full name (including legal form for legal entities):


Herald Investment Management Limited


Contact address (registered office for legal entities):


10/11 Charterhouse Square, London, EC1M 6EE


Phone number:


[phone]


Other useful information (at least legal representative for legal persons):


Andrew Miller


B: Identity of the notifier, if applicable (xvii)


Full name:


See above


Contact address:


Phone number:


Other useful information (e.g. functional relationship with the person or legal
entity subject to the notification obligation)


END

22 March






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