Dialight Regulatory News (DIA)

TR-1: Notifications of Major Interests in Shares

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

Dialight PLC

2. Reason for notification (yes/no)

An acquisition or disposal of voting rights

Yes

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

No

An event changing the breakdown of voting rights

No

Other (please specify):______________

N/A

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

Impax Asset Management Limited

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

Impax Environmental Markets plc

Impax Environmental Markets (Ireland) Fund

Parworld Environmental Opportunities Fund

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

16 April 2007

6. Date on which issuer notified:

27 June 2008

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

5%

8: Notified Details

A: Voting rights attached to shares

Class/type of shares

If possible use ISIN code

Situation previous to the triggering transaction

Resulting situation after the triggering transaction

Number of shares

Number of voting rights

Number of shares

Direct

Number of voting rights

Percentage of voting rights

Direct

Indirect

Direct

Indirect

Ordinary Shares

1,560,946

4.997%

1,660,946

NIL

1,660,946

NIL

5.317%

B: Financial Instruments

Resulting situation after the triggering transaction

Type of financial instrument

Expiration date

Exercise/ conversion period/date 

No. of voting rights that may be acquired (if the instrument exercised/converted)

Percentage of voting rights

Nil

Total (A+B)

Number of voting rights

Percentage of voting rights

1,660,946

5.317%

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

Impax Environmental Markets plc (930,447) shares 2.978%)

Impax Environmental Markets (Ireland) Fund (508,100 shares 1.626%)

Parworld Environmental Opportunities Fund (222,399 shares 0.712%)

Proxy Voting:

10. Name of 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:

Cathryn Buckley

15. Contact telephone name:

01480 447490