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                          December 21, 2023

       Robert Spignesi
       Chief Executive Officer
       Rapid Micro Biosystems, Inc.
       1001 Pawtucket Boulevard West, Suite 280
       Lowell, MA 01854

                                                        Re: Rapid Micro
Biosystems, Inc.
                                                            Registration
Statement on Form S-3
                                                            Filed December 15,
2023
                                                            File No. 333-276081

       Dear Robert Spignesi:

              This is to advise you that we have not reviewed and will not
review your registration
       statement.

               Please refer to Rules 460 and 461 regarding requests for
acceleration. We remind you
       that the company and its management are responsible for the accuracy and
adequacy of their
       disclosures, notwithstanding any review, comments, action or absence of
action by the staff.

                                                        Please contact Benjamin
Richie at 202-551-7857 with any questions.




                          Sincerely,


                          Division of Corporation Finance

                          Office of Industrial Applications and

                          Services
       cc:                                              Adam Johnson