Holding(s) in Company

Oxford Instruments plc has been notified that BT Pension Scheme Trustees
Limited, as trustee of the BT Pension Scheme, has an indirect interest in the
voting rights over 2,857,706 Ordinary Shares of 5p each, which represents 5.77%
of the issued share capital of the Company. Prior to the triggering
transaction, there was an indirect interest in the voting rights over 3,035,622
Ordinary Shares of the Company.

The chain of controlled undertakings through which the voting rights and/or the
financial instruments are effectively held is as follows:

BT Pension Scheme Trustees Limited, as trustee of the BT Pension Scheme
("BTPS") is the parent undertaking of Britel Fund Nominees Limited and Britel
Fund Trustees Limited, which is the parent undertaking of Hermes Fund Managers
Limited ("HFML"). HFML is the parent undertaking of Hermes Equity Ownership
Services Limited ("HEOS") (voting rights: 5.77%)*.

* This notification is also being made in respect of HEOS, which is an indirect
holder of shares for the purpose of DTR 5.2.1(h). The voting rights include the
following: (i) all of the voting rights of the underlying clients of HEOS for
whom it provides voting services; (ii) all of the voting rights attaching to
the direct shareholding of BTPS; (iii) all of the voting rights attaching to
shares managed by Hermes Investment Management Limited ("HIML"); and (iv) the
voting rights attaching to the direct shareholding of BTPS that are managed by
Hermes Sourcecap Limited ("HSL").

HEOS holds the voting rights under a standing proxy contained in agreements for
the provision of voting services to various underlying clients for the purposes
of DTR 5.2.1(h), which includes all the shares owned directly by BTPS, all of
the voting rights attaching to shares managed by HIML and the voting rights
attaching to the direct shareholding of BTPS that are managed by HSL.

All voting rights held on behalf of the above entities are aggregated for the
purposes of DTR 5.2.1(e).

This disclosure is made by BT Pension Scheme Trustees Limited as trustee of the
BT Pension Scheme, which is the ultimate parent undertaking for the purposes of
DTR 5.2.1(e)

25 February 2010

Susan Johnson-Brett

Company Secretary

01865 393324