Rule 8.3 - Detica Group Plc

Arnhold and S. Bleichroeder Advisers, LLC
                  

                                    FORM 8.3

    DEALINGS BY PERSONS WITH INTERESTS IN SECURITIES REPRESENTING 1% OR MORE

                         (Rule 8.3 of the Takeover Code)

1. KEY INFORMATION

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Name of person dealing (Note 1)                         Arnhold and S. Bleichroeder Advisers, LLC
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Company dealt in                                        Detica Group Plc
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Class of relevant security to which the dealings being  2p ordinary shares
 disclosed relate (Note 2)
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Date of dealing                                         August 12, 2008
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2. INTERESTS, SHORT POSITIONS AND RIGHTS TO SUBSCRIBE

(a) Interests and short positions (following dealing) in the class of relevant
security dealt in (Note 3)

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                                                          Long                            Short
-------------------------------------------- ------------------------------ ---------------------------------
                                             Number                     (%) Number                        (%)
-------------------------------------------- ------------------------------ ---------------------------------
(1) Relevant securities
-------------------------------------------- ------------------------------ ---------------------------------
(2) Derivatives (other than options)         1,342,452              (1.15%)
-------------------------------------------- ------------------------------ ---------------------------------
(3) Options and agreements to purchase/sell
-------------------------------------------- ------------------------------ ---------------------------------
Total                                        1,342,452              (1.15%)
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(b) Interests and short positions in relevant securities of the company, other
than the class dealt in (Note 3)

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Class of relevant security:                                Long                     Short
------------------------------------------------ ------------------------- -----------------------
                                                 Number                (%) Number              (%)
------------------------------------------------ ------------------------- -----------------------
(1) Relevant securities
------------------------------------------------ ------------------------- -----------------------
(2) Derivatives (other than options)
------------------------------------------------ ------------------------- -----------------------
(3) Options and agreements to purchase/sell
------------------------------------------------ ------------------------- -----------------------
Total
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(c) Rights to subscribe (Note 3)

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Class of relevant security:                Details
------------------------------------------ -----------------------------------

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3. DEALINGS (Note 4)

(a) Purchases and sales

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Purchase/sale                       Number of securities               Price per unit (Note 5)
----------------------------------- ---------------------------------- ------------------------------------

----------------------------------- ---------------------------------- ------------------------------------
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(b) Derivatives transactions (other than options)

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Product name,        Long/short (Note 6)     Number of securities (Note 7)    Price per unit (Note 5)
e.g. CFD
-------------------- ----------------------- -------------------------------- -----------------------------
CFD                  Long                    77,452                           GBP 4.4083
-------------------- ----------------------- -------------------------------- -----------------------------
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(c) Options transactions in respect of existing securities

(i) Writing, selling, purchasing or varying

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Product name,       Writing, selling,  Number of securities  Exercise Type, e.g.     Expiry  Option money
e.g. call option     purchasing,        to which the option  price     American,     Date    paid/received per
                     varying etc.       relates (Note 7)               European etc.          unit (Note 5)
------------------- ------------------ --------------------- -------- -------------- ------- -------------------

------------------- ------------------ --------------------- -------- -------------- ------- -------------------
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(ii) Exercising

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Product name, e.g. call option      Number of securities               Exercise price per unit (Note 5)
----------------------------------- ---------------------------------- ------------------------------------

----------------------------------- ---------------------------------- ------------------------------------
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(d) Other dealings (including new securities) (Note 4)

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Nature of transaction (Note 8)      Details     Price per unit (if applicable)(Note 5)
----------------------------------- ----------- -----------------------------------------

----------------------------------- ----------- -----------------------------------------
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4. OTHER INFORMATION

Agreements, arrangements or understandings relating to options or derivatives

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Full details of any agreement, arrangement or understanding between the person disclosing and any other
 person relating to the voting rights of any relevant securities under any option referred to on this
 form or relating to the voting rights or future acquisition or disposal of any relevant securities to
 which any derivative referred to on this form is referenced. If none, this should be stated.
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None.
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Is a Supplemental Form 8 attached? (Note 9) NO

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Date of disclosure                                               August 12, 2008
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Contact name                                                     Hayley Nelson
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Telephone number                                                 [phone]
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If a connected EFM, name of offeree/offeror with which connected
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If a connected EFM, state nature of connection (Note 10)
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Notes

The Notes on Form 8.3 can be viewed on the Takeover Panel's website at
www.thetakeoverpanel.org.uk