EXHIBIT 15.6



NOTIFICATION OF TRANSACTIONS OF DIRECTORS, PERSONS DISCHARGING MANAGERIAL RESPONSIBILITY OR CONNECTED
PERSONS



This form is intended for use by an issuer to make a RIS notification
required by DR 3.1.4R(1).



|(1) | An issuer making a notification in respect of a transaction relating to the shares or debentures of the issuer should complete boxes 1 to 16, 23 and 24.
|--- | --------------------------------------------------------------------------------------------------------------------------------------------------------



|(2) | An issuer making a notification in respect of a derivative relating the shares of the issuer should complete boxes 1 to 4, 6, 8,13, 14, 16, 23 and 24.
|--- | ------------------------------------------------------------------------------------------------------------------------------------------------------



|(3) | An issuer making a notification in respect of options granted to a director/person discharging managerial responsibilities should complete boxes 1 to 3 and 17 to 24.
|--- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------



|(4) | An issuer making a notification in respect of a financial instrument relating to the shares of the issuer (other than a debenture) should complete boxes 1 to 4, 6, 8, 9, 11, 13, 14,
16, 23 and 24.
|--- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



Please complete
all relevant boxes should in block capital letters.



1. Name of the issuer



CAMBRIDGE ANTIBODY TECHNOLOGY GROUP PLC



2. State whether the notification relates to (i) a
transaction notified in accordance with DR 3.1.4R(1)(a); or



|(ii) | DR 3.1.4(R)(1)(b) a disclosure made in accordance with section 324 (as extended by section 328) of the Companies Act 1985; or
|---- | -----------------------------------------------------------------------------------------------------------------------------



|(iii) | both (i) and (ii)
|----- | -----------------



|(ii) | 
|---- | 



3. Name of person discharging managerial responsibilities/director



JOHN ASTON



4. State whether notification relates to a person connected with a person discharging managerial responsibilities/director named in

3 and identify the connected person



AS IN 3 ABOVE



---

5. Indicate whether the notification is in respect of a holding of the person referred to in 3 or 4 above or in respect
of a non-beneficial interest



AS IN 3 ABOVE



6. Description of shares (including class), debentures or derivatives or
financial instruments relating to shares



ORDINARY 10 PENCE SHARES



7. Name of registered shareholders(s) and, if more than one, the number of shares held by
each of them



Greenwood Nominees Limited



8. State the nature of the transaction



Purchase of Shares following exercise of option. Sale of
shares to fund exercise.



9. Number of shares,
debentures or financial instruments relating to shares acquired



30,019



10. Percentage of issued class acquired
(treasury shares of that class should not be taken into account when calculating percentage)



0.057%



11. Number of shares, debentures or financial instruments relating to shares disposed



17,579



---

12. Percentage of issued class disposed (treasury shares of that class should not be taken into account when calculating
percentage)



0.033%



13. Price per share or value of transaction



Purchase Price lb.2.87



Sale Price lb.7.20



14. Date and place of transaction



19 December 2005



London



15. Total holding following notification and total percentage holding following notification
(any treasury shares should not be taken

into account when calculating percentage)



72,740



0.137%



16. Date issuer informed of transaction



19 December 2005



If a person discharging managerial responsibilities has been granted options by the issuer complete the following boxes



17 Date of grant

.



---

18. Period during which or date on which it can be exercised



---



19. Total amount paid (if any) for grant of the option



---



20. Description of shares or debentures involved
(class and number)



---



21. Exercise price (if fixed at time of grant) or indication that price is to be fixed at the time of exercise



---



22. Total number of shares or debentures over which options held following notification



---



23. Any additional information



---



24. Name of contact and telephone number for queries



---



Name and signature of duly authorised officer of issuer responsible for making notification



Justin Hoskins



Date of notification



19 December 2005



END



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NOTIFICATION OF MAJOR INTERESTS IN SHARES



1. Name of company



Cambridge Antibody Technology Group plc



2. Name of shareholder having a major interest



Franklin Resources Inc.



3. Please state whether notification indicates that it is in respect of holding of the shareholder named in 2 above or in respect of a non-beneficial interest or in the case of an individual holder if it is a holding
of that persons spouse or children under the age of 18



|                          |  |                |  | 
|------------------------- |  | -------------- |  | 
|Bank of New York          |  | non beneficial |  | 
|JP Morgan Chase Bank      |  | non beneficial |  | 
|Citibank Nominees Limited |  | non beneficial |  | 
|State Street Bank         |  | non beneficial |  | 



4.
Name of the registered holder(s) and, if more than one holder, the number of shares held by each of them



|                          |  |           |  | 
|------------------------- |  | --------- |  | 
|Bank of New York          |  | 24,570    |  | 
|JP Morgan Chase Bank      |  | 1,311,223 |  | 
|Citibank Nominees Limited |  | 14,780    |  | 
|State Street Bank         |  | 840,207   |  | 



5. Number of shares / amount of stock
acquired



not disclosed



6. Percentage of issued class



not known



7. Number of shares / amount of stock disposed



None



8. Percentage of issued class



N/A



9. Class of security



Ordinary 10 pence shares



10. Date of transaction



Not disclosed



---

11. Date company informed



20 December 2005



12. Total holding following this notification



2,190,780



13. Total percentage holding of issued class following this notification



4.136%



14. Any additional information



The disclosure has been made on behalf of Franklin Resources, Inc and its affiliates which includes Franklin Mutual Advisers, LLC and Templeton Worldwide, Inc. Franklin Resources, Inc and its affiliates perform
investment management advisory and related

services for clients on a global basis.



15. Name of contact and telephone number for queries



Justin Hoskins 01223 898589



16. Name and signature of authorised company official responsible for making this
notification



Justin Hoskins, Company
Secretary



Date of notification



20 December 2005



The FSA does not give any express or implied warranty as to the accuracy of this document or
material and does not accept any liability for error or omission. The FSA is not liable for any damages (including, without limitation, damages for loss of business or loss of profits) arising in contract, tort or otherwise from the use of or
inability to use this document, or any material contained in it, or from any action or decision taken as a result of using this document or any such material.



END