Exhibit 15.4



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 DR3.1.4R(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 DR3.1.4R(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 STOCKER



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



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



229



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



0.0004%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



82,894



0.157%



16. Date issuer informed of transaction



1 DECEMBER 2005



If aperson dischargingmanagerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



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



JUSTIN HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005



---

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 DR3.1.4R(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 DR3.1.4R(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



AKE STAVLING



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



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



229



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



0.0004%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



3,050



0.0057%



16. Date issuer informed of transaction



1 DECEMBER 2005



If aperson discharging managerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



Name and signature of duly authorised officer ofissuerresponsible
for making notification



JUSTIN HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005



---

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 DR3.1.4R(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 DR3.1.4R(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



SIR AARON KLUG



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



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



229



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



0.0004%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



28,635



0.055%



16. Date issuer informed of transaction



1 DECEMBER 2005



If aperson discharging managerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



Name and signature of duly authorised officer ofissuerresponsible for making notification



JUSTIN
HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005



---

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 DR3.1.4R(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 DR3.1.4R(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



PETER RINGROSE



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



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



229



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



0.0004%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



3,870



0.007%



16. Date issuer informed of transaction



1 DECEMBER 2005



If aperson discharging managerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



Name and signature of duly authorised officer ofissuerresponsible
for making notification



JUSTIN HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005



---

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 DR3.1.4R(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 DR3.1.4R(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



PROFESSOR CHRISTOPHER MARSHALL



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



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



229



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



0.0004%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



935



0.0017%



16. Date issuer informed of transaction



1 DECEMBER 2005



If aperson discharging managerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



Name and signature of duly authorised officer ofissuerresponsible
for making notification



JUSTIN HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005



---

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 DR3.1.4R(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 DR3.1.4R(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



DR PAUL NICHOLSON



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



DR PAUL NICHOLSON



---

8. State the nature of the transaction



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



551



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



0.001%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



11,314



0.021%



16. Date issuer informed of transaction



1 DECEMBER 2005



If aperson discharging managerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



Name and signature of duly authorised officer ofissuerresponsible
for making notification



JUSTIN HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005



---

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 DR3.1.4R(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 DR3.1.4R(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



PROFESSOR UWE BICKER



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



PROFESSOR UWE BICKER



---

8. State the nature of the transaction



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



229



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



0.0004%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



6,753



0.013%



16. Date issuer informed of transaction



15 SEPTEMBER 2005



If aperson discharging managerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



Name and signature of duly authorised officer ofissuerresponsible
for making notification



JUSTIN HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005



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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 DR3.1.4R(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 DR3.1.4R(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



PROFESSOR JOHN BROWN



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



QUARTERLY PAYMENT OF PART OF DIRECTORS FEES IN LIEU OF CASH CONSIDERATION (SEE NOTES AT 23)



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



47



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



0.00008%



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



NIL



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



NIL



13. Price per share or value of transaction



£6.80



14. Date and place of transaction



1 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)



47



0.00008%



16. Date issuer informed of transaction



1 DECEMBER 2005



If aperson discharging managerial responsibilitieshas been granted options by theissuercomplete 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



THE PRACTICE OF ISSUING SHARES IN LIEU OF PART OF THE BASIC DIRECTORS FEE HAS BEEN
ESTABLISHED BY THE COMPANY FOR SOME TIME. IN NOVEMBER 2004 THE BOARD RESOLVED THAT SUCH ISSUE OF SHARES WOULD OCCUR ON A QUARTERLY RATHER THAN AN ANNUAL BASIS. THE SHARE PRICE USED IS THE AVERAGE CLOSING PRICE OF ONE CAT SHARE FOR THE THREE TRADING
DAYS PRECEDING 1 DECEMBER 2005.



24. Name of contact and telephone number for
queries



JUSTIN HOSKINS, 01223 898589



Name and signature of duly authorised officer ofissuerresponsible
for making notification



JUSTIN HOSKINS, COMPANY SECRETARY



Date of notification



1 DECEMBER 2005