Cellectis Announces Participation in Five Investor Conferences Published on August 26, 2021 in New York, NY BACK TO ALL PRESS RELEASES August 26, 2021 – New York – Cellectis S.A. (NASDAQ: CLLS – EURONEXT GROWTH: ALCLS) (the “Company”), a gene-editing platform company with clinical-stage immuno-oncology programs using allogeneic chimeric antigen receptor (CAR)-T cells and gene therapy programs for monogenic diseases, today announced that management plans to participate in five virtual investor conferences. 11th Annual Biotech Symposium (Goldman Sachs) Date: Tuesday, September 7, 2021 Time: 8AM-6PM (GMT) Citi’s 16th Annual Biopharma Conference 2021 Date: Thursday, September 9, 2021 Time: 10:40AM ET Wells Fargo Healthcare Conference Date: Friday, September 10, 2021 Time: 9:20AM ET H.C. Wainwright 23rd Annual Global Investment Conference Date: Monday, September 13, 2021 Time: 7AM ET Baird 2021 Global Healthcare Conference Date: Wednesday, September 15, 2021 Time: 9:05 AM ET Live webcasts of these events and a replay of these webcasts will be available under the “Events and Webcasts” section on the Investor page of the of the Company’s at website: https://www.cellectis.com/en/investors/events-and-webcasts/ DOWNLOAD THE PDF FILE Press contacts For more information on any story, or for press enquiries, get in touch with our Media Team. CONTACT US LEGAL NOTICEGLOSSARYMEDIA LIBRARYCONTACTCOMMUNITY GUIDELINES Subsidiary: Calyxt Inc.