SC 13G/A

0001193125-12-043947.txt : 20120207 0001193125-12-043947.hdr.sgml : 20120207 20120207170659 ACCESSION NUMBER: 0001193125-12-043947 CONFORMED SUBMISSION TYPE: SC 13G/A PUBLIC DOCUMENT COUNT: 1 FILED AS OF DATE: 20120207 DATE AS OF CHANGE: 20120207 GROUP MEMBERS: BIOTECH TARGET N.V. SUBJECT COMPANY: COMPANY DATA: COMPANY CONFORMED NAME: IMMUNOGEN INC CENTRAL INDEX KEY: 0000855654 STANDARD INDUSTRIAL CLASSIFICATION: PHARMACEUTICAL PREPARATIONS [2834] IRS NUMBER: 042726691 STATE OF INCORPORATION: MA FISCAL YEAR END: 0630 FILING VALUES: FORM TYPE: SC 13G/A SEC ACT: 1934 Act SEC FILE NUMBER: 005-40774 FILM NUMBER: 12578665 BUSINESS ADDRESS: STREET 1: 830 WINTER ST CITY: WALTHAM STATE: MA ZIP: 02451 BUSINESS PHONE: (781)895-0600 MAIL ADDRESS: STREET 1: 830 WINTER ST CITY: WALTHAM STATE: MA ZIP: 02451 FILED BY: COMPANY DATA: COMPANY CONFORMED NAME: BB BIOTECH AG CENTRAL INDEX KEY: 0000924223 STANDARD INDUSTRIAL CLASSIFICATION: UNKNOWN SIC - 0000 [0000] STATE OF INCORPORATION: V8 FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: SC 13G/A BUSINESS ADDRESS: STREET 1: VODERGASSE 3 STREET 2: SWITZERLAND CITY: SCHAFFHAUSEN STATE: V8 ZIP: CH-8300 BUSINESS PHONE: 411724 59 59 MAIL ADDRESS: STREET 1: VODERGASSE 3 STREET 2: SWITZERLAND CITY: SCHAFFHAUSEN STATE: V8 ZIP: CH-8300 SC 13G/A 1 d296084dsc13ga.htm SC 13G/A SC 13G/A

United States

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

IMMUNOGEN, INC.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

45253H101

(CUSIP Number)

December 31, 2011

(Date of Event Which Requires Filing This Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

¨ Rule 13d-1(b)

x Rule 13d-1(c)

¨ Rule 13d-1(d)

The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 45253H101


1.	Names of Reporting Persons BB Biotech AG
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a) x (b) ¨
3.	SEC Use Only
4.	Citizenship or Place of Organization Switzerland
Number of Shares Beneficially Owned by Each Reporting Person with:		5.	Sole Voting Power 0
		6.	Shared Voting Power 4,000,000
		7.	Sole Dispositive Power 0
		8.	Shared Dispositive Power 4,000,000
9.	Aggregate Amount Beneficially Owned by Each Reporting Person 4,000,000
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares [ ]
11.	Percent of Class Represented by amount in Row (9) 5.23%
12.	Type of Reporting Person (See Instructions) HC,CO

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CUSIP No. 45253H101


1.	Names of Reporting Persons Biotech Target N.V. I.R.S. Identification Nos. of above persons (entities only): N/A
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a) x (b) ¨
3.	SEC Use Only
4.	Citizenship or Place of Organization Netherlands Antilles
Number of Shares Beneficially Owned by Each Reporting Person with:		5.	Sole Voting Power 0
		6.	Shared Voting Power 4,000,000
		7.	Sole Dispositive Power 0
		8.	Shared Dispositive Power 4,000,000
9.	Aggregate Amount Beneficially Owned by Each Reporting Person 4,000,000
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares [ ]
11.	Percent of Class Represented by amount in Row (9) 5.23%
12.	Type of Reporting Person (See Instructions) CO

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Item 4. Ownership

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

(a)

Amount beneficially owned: 4,000,000

(b)

Percent of class: 5.23%

(c)

Number of shares as to which the person has:

(i)

Sole power to vote or to direct the vote 0

(ii)

Shared power to vote or to direct the vote 4,000,000

(iii)

Sole power to dispose or to direct the disposition of 0

(iv)

Shared power to dispose or to direct the disposition of 4,000,000

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Item 10. Certification

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

SIGNATURES

After reasonable inquiry and the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

BB Biotech AG



Date: January 31, 2012	By:	/s/ Michael Hutter
		Signatory Authority

	Name:	Michael Hutter

	Title:	Signatory Authority



Date: January 31, 2012	By:	/s/ Pascal Schmucki
		Signatory Authority

	Name:	Pascal Schmucki

	Title:	Signatory Authority

Biotech Target N.V.



Date: January 31, 2012	By:	/s/ Michael Hutter
		Signatory Authority

	Name:	Michael Hutter

	Title:	Signatory Authority



Date: January 31, 2012	By:	/s/ Pascal Schmucki
		Signatory Authority

	Name:	Pascal Schmucki

	Title:	Signatory Authority

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Exhibit Index

Exhibit A: Agreement by and between BB Biotech AG and Biotech Target N.V. with respect to the filing of this disclosure statement.*

* Previously filed as an exhibit to BB Biotech AG and Biotech Target N.V.’s Schedule 13G filed with the Securities and Exchange Commission on May 14, 2010.

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