Notification of major interest in shares

TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARES

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

Regenersis PLC

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

An acquisition or disposal of voting rights

 YES

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

NO

An acquisition or disposal of instruments with similar economic effect to qualifying financial instruments

 NO

An event changing the breakdown of voting rights

 N/A

Other (please specify):

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

 Impax Asset Management Limited

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

Impax Enviromental Markets plc, Impax Enviromental Markets Ireland, The Eviroment Agency Fund

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

 20 January 2011

6. Date on which issuer notified:

 21 January 2011

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

 11%, 12%, 13%

8. Notified details:

A: Voting rights attached to shares

Class/type ofshares

if possible usingthe ISIN CODE

Situation previousto the triggeringtransaction

Resulting situation after the triggering transaction

NumberofShares

NumberofVotingRights

Numberof shares

Number of votingrights

% of voting rights

Direct

Direct

Indirect

Direct

Indirect

 6,018,014

13.43%

4,518,014

Nil

4,518,014

Nil

10.08%

 Ordinary Shares

BBG000DN20X5

B: Financial Instruments

Resulting situation after the triggering transaction

Type of financialinstrument

Expirationdate

Exercise/ConversionPeriod

Number of votingrights that may beacquired if theinstrument isexercised/ converted.

% of votingrights

 Nil

Total (A+B+C)

Number of voting rights

Percentage of voting rights

 4,518,014

 10.08%

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

Impax Environmental Markets Plc (2,713,479 shares 6.0542%)

Impax Environmental Markets Ireland (1,354,535 shares 3.0222%)

The Environment Agency Fund (450,000 shares 1.0040%)

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:

 N/A

14. Contact name:

 Compliance Officer

15. Contact telephone number:

 +44 (0) 20 7434 1122

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

Full name

(including legal form of legal entities)

Impax Asset Management Limited

Contact address

(registered office for legal entities)

Mezzanine Floor

Pegasus House

37-43 Sackville Street

London

W1S 3EH

Phone number & email

+44 (0) 20 7434 1122

[email protected]

Other useful information

(at least legal representative for legal persons)

B: Identity of the notifier, if applicable

Full name

Impax Operations Department

Contact address

Mezzanine Floor

Pegasus House

37-43 Sackville Street

London

W1S 3EH

Phone number & email

44 (0) 20 7434 1122

[email protected]

Other useful information

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

C: Additional Information