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EXHIBIT 23.1
CONSENT OF INDEPENDENT ACCOUNTANTS
We consent to the incorporation by reference in this Amendment No. 2 to the
Registration Statement of ImmunoGen, Inc. on Form S-3 (File No. 333-48042) to
register 4,600,000 shares of common stock of our report, dated July 28, 2000,
except for Note 14 as to which the date is September 7, 2000 on our audits of
the consolidated financial statements of ImmunoGen, Inc. as of June 30, 2000 and
1999 and for each of the three years in the period ended June 30, 2000, which
report is included in the Company's 2000 Annual Report on Form 10-K.
We also consent to the reference to our Firm in the Registration Statement
under the caption "Experts".
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/s/ PRICEWATERHOUSECOOPERS LLP
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PricewaterhouseCoopers LLP
Boston, Massachusetts
November 15, 2000
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