Diploma Regulatory News (DPLM)

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:

Diploma plc

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

An acquisition or disposal of voting rights

No

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

No

Other (please specify):

See additional information below

Yes

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

F&C Asset Management plc

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

See Box 9 below

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

N/A (see additional information below)

6. Date on which issuer notified:

24/09/2010

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

N/A (see additional information below)

8. Notified details:

A: Voting rights attached to shares

Class/type of shares

if possible using the ISIN CODE

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

GB0001826634

n/a

n/a

9,358,756

-

9,358,756

-

8.27%

GBP0.05

(as at 23/09/2010)

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financial instrument

Expiration date

Exercise/ Conversion Period

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

% of voting rights

C: Financial Instruments with similar economic effect to Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financial instrument

Exercise price

Expiration date

Exercise/ Conversion period

Number of voting rights instrument refers to

% of voting rights

Nominal

Delta

Total (A+B+C)

Number of voting rights

Percentage of voting rights

9,358,756 (as at 23/09/2010)

8.27%

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

 F&C Asset Management plc:

Proxy Voting:

10. Name of the proxy holder:

F&C Asset Management plc

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:

The disclosure made on 1 September 2010 outlining that F&C's aggregate position fell below 5% was incorrect due to a system error. As of 23 September 2010 F&C's aggregate holding is 8.27%.

14. Contact name:

Marrack Tonkin, Company Secretary, F&C Asset Management plc

15. Contact telephone number:

0131 718 1247