Holding(s) in Company

17 Dec 2010 11:25

For filings with the FSA include the annex For filings with issuer exclude the annex TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARESi

1. Identity of the issuer or the underlying UNITED UTILITIES GROUP PLC issuer

of existing shares to which voting rights are attached: ii

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

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

An event changing the breakdown of voting rights Other (please specify): 3. Full name of person(s) subject to Deutsche Bank AG the notification obligation: iii 4. Full name of shareholder(s) (if different from 3.):iv 5. Date of the transaction and date 14/12/2010 on which the threshold is crossed or reached: v 6. Date on which issuer notified: 15/12/2010 7. Threshold(s) that is/are crossed 3% or reached: vi, vii 8. Notified details: A: Voting rights attached to shares viii, ix

Class/type Situation previous Resulting situation after the triggering of

to the triggering transaction shares transaction Number Number Number Number of voting % of voting if possible of of of rights rights x using Shares Voting shares the ISIN Rights CODE Direct xi Indirect Direct Indirect xii

GB00B39J2M42 37,928,379 37,928,379 Below 3% Below 3% Below 3% Below Below 3%

3% B: Qualifying Financial Instruments Resulting situation after the triggering transaction Type of financial Expiration Exercise/ Number of voting % of voting instrument date xiii Conversion Period rights that may be rights xiv acquired if the instrument is exercised/ converted.

C: Financial Instruments with similar economic effect to Qualifying Financial Instruments xv, xvi

Resulting situation after the triggering transaction Type of Exercise Expiration Exercise Number of voting % of voting rights financial price date xvii / rights instrument xix, xx instrument Conversion refers to period xviii Nominal Delta Total (A+B+C) Number of voting rights Percentage of voting rights Below 3% Below 3%

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

Proxy Voting: 10. Name of the proxy holder: 11. Number of voting rights proxy holder will cease to hold: 12. Date on which proxy holder will cease to hold voting rights: 13. Additional information: 14. Contact name: Dirk Young

15. Contact telephone number: +44(20)754-57177