United States securities and exchange commission logo June 3, 2021 Susan Kim Chief Financial Officer Pacific Biosciences of California, Inc. 1305 O'Brien Drive Menlo Park, CA 94025 Re: Pacific Biosciences of California, Inc. Form 10-K for the Fiscal Year Ended December 31, 2020 Filed on February 26, 2021 File No. 001-34899 Dear Ms. Kim: We have completed our review of your filing. 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. Sincerely, Division of Corporation Finance Office of Life Sciences