1.

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

CELOXICA HOLDINGS 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 (specify):

Final deadline re DTR 5

(X)

3.

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

Herald Investment Management Limited

4.

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

Not needed

5.

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

n/a – see (2) above

6.

Date on which issuer notified:

20 March 2007

7.

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

7%

8.

Notified details:

Class/type of shares (if possible using the ISIN code)

Ordinary 1p (GB00B0L9TZ33)

Situation previous to the triggering transaction

Resulting situation after the triggering transaction

Number of Shares

Number of Voting Rights

Number of shares

Number of voting rights

% of voting rights

Direct

Direct

Indirect

Direct

Indirect

5,137,500 (7.31%)

5,137,500
(7.31%)

5,137,500

7.31%

Type of financial instrument

Expiration date

Exercise/Conversion Period/Date

Number of voting rights that may be acquired if the instrument is exercised/converted

% of voting rights

Number of voting rights

% of voting rights

5,137,500

7.31%

9.

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

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

Herald Investment Trust (in the name of Bank of New York (OCS Nominees Limited)

5,137,500  (7.31%)

Total for Funds under the management of Herald Investment Management Limited

5,137,500  (7.31%)

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:

020 7553 6308