Monthly information on share capital and company voting rights

(Article 223-16 of General Regulation of the French financial markets authority)NEW YORK, May 10, 2021 (GLOBE NEWSWIRE) — Listing market: Euronext Growth ISIN code: FR0010425595 DateTotal number of sharesin the capitalTotal number of voting rights04/30/202145,461,31051,526,159 About CellectisCellectis is developing the first of its kind allogeneic approach for CAR-T immunotherapies in oncology, pioneering the concept of off-the-shelf and ready-to-use gene-edited CAR T-cells to treat cancer patients. As a clinical-stage biopharmaceutical company with over 21 years of expertise in gene editing, Cellectis is developing life-changing product candidates utilizing TALEN®, its gene editing technology, and PulseAgile, its pioneering electroporation system to harness the power of the immune system in order to target and eradicate cancer cells. As part of its commitment to a cure, Cellectis remains dedicated to its goal of providing life-saving UCART product candidates to address unmet needs for multiple cancers including acute myeloid leukemia (AML), B-cell acute lymphoblastic leukemia (B-ALL) and multiple myeloma (MM). Cellectis headquarters are in Paris, France, with additional locations in New York and Raleigh, North Carolina. Cellectis is listed on the Nasdaq Global Market (ticker: CLLS) and on Euronext Growth (ticker: ALCLS). For more information, visit www.cellectis.com. Follow Cellectis on social media: @cellectis, LinkedIn and YouTube. TALEN® is a registered trademark owned by Cellectis. For further information, please contact: Media contacts:Pascalyne Wilson, Communications Manager, +33776991433, [email protected] IR contact:Simon Harnest, SVP, Corporate Strategy and Finance, 646-385-9008, [email protected] Attachment Voting_Rights_PR_April_EN_docx