Exhibit 10.52
HEADS OF AGREEMENT:
IMMUNOGEN /GENENTECH COLLABORATIVE AGREEMENT
A. EFFECTIVE DATE: The effective date of this Heads of Agreement ("HEADS OF AGREEMENT") shall be
as of May 2, 2000 (the "EFFECTIVE DATE").
B. PARTIES: The parties to this Heads of Agreement are Genentech, Inc., a Delaware corporation with offices
located at 1 DNA Way, South San Francisco, CA 94080 ("GENENTECH") and ImmunoGen, Inc., a
Massachusetts corporation with offices located at 333 Providence Highway, Norwood, MA 02062
("IMMUNOGEN"). Genentech and ImmunoGen are each also referred to herein singly as a "PARTY" and
collectively as the "PARTIES".
C. PREAMBLE:
1. ImmunoGen owns or controls certain proprietary technology (including patent rights and know-how) relating
to the conjugation of maytansine derivatives such as DM1 to binding proteins;
2. Genentech owns or controls certain proprietary technology (including patent rights and know-how) relating to
antibodies and other binding proteins;
3. As of the Effective Date, the Parties have entered into an exclusive license agreement pertaining to the use of
ImmunoGen's proprietary toxin conjugation technology with a particular antibody and related binding proteins
(the "GENENTECH LICENSE");
4. Concurrently with such Genentech License, the Parties have also agreed upon the terms and conditions for a
broader arrangement relating to the conjugation of a larger array of antibodies and binding proteins to maytansine
derivatives such as DM1; and
5. The Parties desire to enter into this Heads of Agreement to evidence their agreement to the terms and
conditions, set forth hereinbelow, relating to such broader arrangement.
D. AGREEMENT: The Parties intend shortly to enter into a detailed agreement (the "AGREEMENT") relating to
the above-referenced broader arrangement, under which Genentech may select and test a number of antibodies
and other binding proteins together with ImmunoGen's conjugation technology, and may acquire exclusive option
rights and/or exclus