Additional Relevant Details
The Notes will be senior unsecured obligations of ImmunoGen, and interest will be payable semi-annually. The Notes will be convertible by the holders at their option at any time prior to the close of business on the business day immediately preceding the maturity date of July 1, 2021. Upon conversion, the holders will receive shares of ImmunoGen's common stock. Upon specified corporate events, subject to certain conditions, holders may require ImmunoGen to repurchase for cash all or part of their Notes at a price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest. Following certain corporate events that occur prior to the stated maturity date, ImmunoGen will increase the conversion rate for a holder who elects to convert the Notes in connection with such a corporate event in certain circumstances. The interest rate, initial conversion rate and other terms of the Notes will be determined at the time of pricing of the offering.