Holding(s) in Company

HALMA p.l.c.

NOTIFICATION OF MAJOR INTERESTS IN SHARES

In conformity with the Transparency Directive, Halma p.l.c. ('Halma') is required to announce to the market the receipt of notifications of major interests in shares. Halma received the notice below on 30 April 2010 in respect of Massachusetts Financial Services Company.

Carol Chesney

Company Secretary, Halma p.l.c.

Tel +44 (0)1494 721111

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:

Halma p.l.c.

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 the notification obligation:

Massachusetts Financial Services Company

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

MFS invests in securities of the issuer on behalf of its various mutual funds and institutional account clients.

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

28 April 2010

6. Date on which issuer notified:

30 April 2010

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 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

GB0004052071

20,537,397

20,537,397

18,950,413

5.04%

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

18,950,413

5.04%

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

Halma p.l.c. - 0405207

Holdings as of 28 April 2010

Entity

MFS Investment Management (MFS)

Holding

6,135,689

Percentage held

1.63%

MFS Institutional Advisors, Inc. (MFSI)

439,080

0.12%

MFS International Ltd. (MIL)

2,181,784

0.58%

MFS International (U.K.) Limited (MIL U.K.)

10,190,978

2.71%

MFS International Management K.K. (MIM K.K.)

2,882

0.00%

Notifiable interest

18,950,413

5.04%

Shares outstanding

376,524,001

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:

14. Contact name:

15. Contact telephone number:

Annex to Notification of Major Interests in Shares

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

Full name (including legal form for legal entities)

Massachusetts Financial Services Co.

Contact address (registered office for legal entities)

500 Boylston Street

Boston, MA 02116

USA

Phone number & email

617-954-5822

Other useful information (at least legal representative for legal persons)

Christopher Bohane