Rule 8.3 - London Stock Exchange PLC

Kinetics/Horizon
                  

                           AMENDED DISCLOSURE 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)                   Kinetics Asset Management, Inc.
                                                  Horizon Asset Management, Inc.
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Company dealt in                                  London Stock Exchange Group PLC
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Class of relevant security to which the dealings  Ordinary Shares
 being disclosed relate (Note 2)
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Date of dealing                                   21 November 2006
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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
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                                          Number     (%)                Number     (%)
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(1) Relevant securities                   12,683,797 5.9487%            0
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(2) Derivatives (other than options)      0                             0
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(3) Options and agreements to
 purchase/sell                            0                             0
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Total                                     12,683,797 5.9487%            0
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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: Class B        Long                          Short
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                                          Number     (%)                Number     (%)
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(1) Relevant securities                   91,880   1.1%                 0
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(2) Derivatives (other than options)      0                             0
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(3) Options and agreements to
 purchase/sell                            0                             0
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Total                                     91,880   1.1%                 0
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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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Purchase                           1,705                             $24.95 USD
Purchase                           450                               $25.25 USD
Purchase                           410                               $24.85 USD
Sale                               1,051                             $24.55 USD
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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
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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,        Number of          Exercise  Type, e.g.   Expiry    Option money
e.g. call option    selling,        securities to     price      American,   date      paid/received per unit (Note 5)
                    purchasing,     which the option             European
                    varying etc.    relates (Note 7)             etc.
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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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Is a Supplemental Form 8 attached? (Note 9) NO

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Date of disclosure                                          08/12/06
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Contact name                                                Andrew Fishman
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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