Holding(s) in Company

For filings with the FSA include the annex

For filings with issuer exclude the annex 

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:

ARM Holdings 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):______________

No

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

Wellington Management Company, LLP

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

HSBC Global Custody Nominee (UK) Limited JP Morgan Chase Nominees Limited Mellon Nominees (UK) Ltd. State Street Nominees Limited

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

31 October 2008

6. Date on which issuer notified:

03 November 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

Number of voting rights

Percentage of voting rights

Direct

Indirect

Direct

Indirect

GB00005958599 Common Stock

63,857,117

63,857,117

62,630,887

62,630,887

4.98%

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

Total (A+B)

Number of voting rights

Percentage of voting rights

62,630,887

4.98%

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

HSBC Global Custody Nominee (UK) Limited - 7,471,308 shares JP Morgan Chase Nominees Limited - 9,849,872 shares Mellon Nominees (UK) Ltd. - 9,657,464 shares

State Street Nominees Limited - 35,652,243 shares

Proxy Voting:

10. Name of 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:

JOANNE O'SULLIVAN 133676

15. Contact telephone number:

00441223406122