Certain Common Stock of Rubius Therapeutics, Inc. are subject to a Lock-Up Agreement Ending on 14-JAN-2019. These Common Stock will be under lockup for 181 days starting from 17-JUL-2018 to 14-JAN-2019. Details: The companies directors and executive officers and holders of common stock have signed a lock-up agreement that prevent us and them from selling any of common stock or any securities convertible into or exercisable or exchangeable for common stock for a period of not less than 180 days from the date of this prospectus without the prior written consent of the representatives of the underwriters, subject to certain exceptions.