FORM 6-K

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Report of Foreign Private Issuer

Pursuant to Rule 13a - 16 or 15d - 16 of

the Securities Exchange Act of 1934

For the month of June, 2004

Commission File Number: 1-10817

CELLTECH GROUP PLC

(Translation of registrant's name into English)

208 Bath Road, Slough, Berkshire SL1 3WE ENGLAND

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

Form 20-F X Form 40-F

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes No X

(If "Yes" is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82-________).

Enclosure: ~~ADR~~Holding(s) ~~Trading~~in ~~Halt~~Company

~~Celltech~~SCHEDULE Group plc (symbol: CLL) announces today that it has received notification from the New York Stock Exchange (the "NYSE") that, in accordance with its standard operating procedures, the NYSE intends to halt trading of Celltech's American Depositary Receipts as of 10~~:00 a.m. (New York City time) today as such time is the close of the initial offer period for the recommended cash tender offer by UCB S.A. for the entire issued share capital of Celltech.~~

~~Celltech~~NOTIFICATION ~~has~~OF ~~been~~MAJOR ~~informed~~INTERESTS ~~that~~IN the halt of trading shall continue until such time as UCB makes public announcement of the level of acceptances as of the close of the initial offer period and its intention whether to extend the initial offer period or commence the subsequent offer period. In accordance with the provisions of the U.K. City Code on Takeovers and Mergers and the Securities Exchange Act of 1934 and as set out in the Offer Document dated May 19, 2004, UCB intends to make such announcement no later than 8:00 a.m. (London time) in the United Kingdom, and by 8:00 a.m. (New York City time) in the United States, on June 18, 2004.SHARES

~~Enquiries:~~1. Name of company Celltech Group plc

~~Richard~~2. ~~Bungay Director~~Name of ~~Corporate~~shareholder ~~Communications +44~~having ~~(0)1753~~a ~~534655 John~~major ~~Slater Company Secretary~~interest ~~+44~~UCB ~~(0)1753 534655~~S.A.

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
As in 2 above

4. Name of the registered holder(s) and, if more than one holder, the number of shares held by each of them
The identities of the current registered holders of the shares to which this notification relates is unknown, but it is intended that the shares should be registered in the name of UCB S.A.

5. Number of shares / amount of stock acquired
34,308,106 (since last notification)

6. Percentage of issued class
12.32%

7. Number of shares / amount of stock disposed
N/a

8. Percentage of issued class
N/a

9. Class of security
50p Ordinary Shares

10. Date of transaction
17 June 2004

11. Date company informed
18 June 2004

12. Total holding following this notification
83,493,000

13. Total percentage holding of issued class following this notification
29.99%

14. Any additional information

15. Name of contact and telephone number for queries
Anita Dowling (01753) 777106

16. Name and signature of authorised company official responsible for making this notification
J A D Slater

Date of notification

18 June 2004

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.

SCHEDULE 10

NOTIFICATION OF MAJOR INTERESTS IN SHARES

1. Name of company

Celltech Group plc

2. Name of shareholder having a major interest

AMVESCAP PLC as agent for the ICVC named below.

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

Unknown

5. Number of shares / amount of stock acquired

Unknown

6. Percentage of issued class

Unknown

7. Number of shares / amount of stock disposed

N/a

8. Percentage of issued class

N/a

9. Class of security

Ordinary 50p shares

10. Date of transaction

Unknown

11. Date company informed

18 June 2004

12. Total holding following this notification

Unknown

13. Total percentage holding of issued class following this notification

Unknown

14. Any additional information

NO LONGER HAVE A NOTIFIABLE INTEREST.

15. Name of contact and telephone number for queries

Anita Dowling Tel. 01753 777106

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

J A D Slater

Date of notification

18 June 2004

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

CELLTECH GROUP PLC
(Registrant)

                                                                                                                                                           By: /s/ PETER ALLEN
                                                                                                                                                           Peter Allen
                                                                                                                                                           Chief Financial Officer

Dated: 1718 June, 2004

Filing Compare · CELLTECH GROUP PLC