JOINT FILING AGREEMENTJoint Filing Agreement • February 16th, 2016 • Baker Bros. Advisors Lp • Pharmaceutical preparations
In accordance with Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree that this Statement on Schedule 13G relating to the Common Stock of ImmunoGen, Inc. is being filed with the Securities and Exchange Commission on behalf of each of them.
