ImmunoGen, Inc. (Nasdaq: IMGN), a biotechnology company that develops novel anticancer therapeutics using its antibody-drug conjugate (ADC) technology, announced today that it has again been named one of The Boston Globe’s Top Places to Work. The Boston Globe’s 2013 Top Places to Work survey, conducted by WorkplaceDynamics, measured responses of employees from numerous organizations in Massachusetts to statements regarding six key factors related to employee happiness, including company direction, execution, employee connection, work load and responsibility, management, and pay and benefits. More than 76,000 individuals responded to the survey. Among survey respondents, greatest importance was placed on aspects related to employee appreciation and feeling that their work is meaningful. WorkplaceDynamics also found that, of all the cities surveyed, employees in the Boston area were most enthusiastic about their companies, making Boston the top of the Top Places to Work. Daniel Junius, President and CEO, commented, “ImmunoGen is focused on developing and advancing meaningful new treatments for cancer. To succeed in this mission, it is essential that we hire and retain top quality people. We are extremely pleased that our supportive culture and other key aspects of working at ImmunoGen are reflected in the survey responses and that our company has again been recognized as one of The Boston Globe’s Top Places to Work.” About ImmunoGen, Inc. ImmunoGen, Inc. develops targeted anticancer therapeutics. The Company’s ADC technology uses a tumor-targeting engineered antibody to deliver one of ImmunoGen's highly potent cancer-cell killing agents specifically to tumor cells. The most advanced compound with ImmunoGen’s ADC technology is Roche’s Kadcyla ®, which is marketed in the US by Genentech and is also gaining approvals internationally. Additional compounds are in clinical testing by ImmunoGen and through the Company’s partnerships with Amgen, Bayer HealthCare, Biotest and Sanofi. More information about ImmunoGen can be found at www.immunogen.com. Kadcyla ® is a registered trademarks of Genentech, Inc., a member of the Roche Group.