Holding in Company

Diploma PLC
12 January 2001


LETTER TO:     COMPANY ANNOUNCEMENTS OFFICE

We enclose a copy of a letter received today from Unicorn Asset Management
Limited notifying their interest in 10.22% of our issued share capital.

LETTER FROM:   DIPLOMA PLC



LETTER TO:     DIPLOMA PLC
LETTER DATED:  11 JANUARY 2001

In accordance with the provisions of the Companies Act 1985 and the Disclosure
of Interests in Shares (Amendment) Regulation 1993, I am writing to advise you
of the following transactions affecting the notifiable interest of Unicorn Asset
Management Limited in your company:

Eaglet Investment Trust                    2,040,081
(held HSBC Global Nominees Ltd a/c Eaglet)

Acorn Income Fund Limited                    395,365
(held Forest Nominees Limited a/c GCA15)

Premier UK Small Companies Fund              136,250


Unicorn Asset Management Limited has a notifiable interest in 2,571,696 shares
in your company representing 10.22% of shares of this class. This interest
arises purely from the status of Unicorn Asset Management Limited as investment
manager to the above two companies. Unicorn Asset Management Limited is not the
beneficial owner of the shares and should not be identified as such.

LETTER FROM:   UNICORN ASSET MANAGEMENT LTD