Third Quarter 2021 Financial Results

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer Pursuant to Rule 13a-16 or 15d-16 under the Securities Exchange Act of 1934

Date of Report: November 4, 2021

Commission File Number: 001-36891

Cellectis S.A.

(Exact Name of registrant as specified in its charter)

8, rue de la Croix Jarry

75013 Paris, France

[phone]

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

Form 20-F☒

Form 40-F☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

Exhibits

The following document, which is attached as an exhibit hereto, is incorporated by reference herein.

This report on Form 6-K shall be deemed to be incorporated by reference in the registration statements of Cellectis S.A. on Form F-3 (No. 333-238881) and Form S-8 (Nos. 333-204205,333-214884,333-222482 and 333-227717), to the extent not superseded by documents or reports subsequently filed.

Exhibit

Title

99.1 Cellectis S.A.'s interim report for the three and nine-month periods ended September 30, 2021. 2

EXHIBIT INDEX

Exhibit

Title

99.1 Cellectis S.A.'s interim report for the three and nine-monthperiods ended September 30, 2021.3

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	CELLECTIS S.A.
	(Registrant)
November 4, 2021	By: /s/ André Choulika
		André Choulika
		Chief Executive Officer
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Exhibit 99.1

PRELIMINARY NOTE

The unaudited condensed Consolidated Financial Statements for the three and nine-month periods ended September 30, 2021, included herein, have been prepared in accordance with International Accounting Standard 34 ("IAS 34" )- Interim Financial Reporting as issued by the International Accounting Standards Board ("IASB"). The consolidated financial statements are presented in U.S. dollars. All references in this interim report to "$" and "U.S. dollars mean U.S. dollars and all references to "€" and "euros" mean euros, unless otherwise noted.

This interim report, including "Management's Discussion and Analysis of Financial Condition and Results of Operations," contains forward- looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and Section 27A of the Securities Act. All statements other than present and historical facts and conditions contained in this interim report, including statements regarding our future results of operations and financial position, business strategy, plans and our objectives for future operations, are forward-looking statements. When used in this interim report, the words "anticipate," "believe," "can," "could," "estimate," "expect," "intend," "is designed to," "may," "might," "plan," "potential," "predict," "objective," "should," or the negative of these and similar expressions identify forward-looking statements. These forward-looking statements are subject to numerous risks and uncertainties and are made in light of information currently available to us. Actual results, performance or events may differ materially from those projected in any forward-looking statement. Many important factors may adversely affect such forward-looking statements and cause actual results to differ from those in any forward-looking statement, including, without limitation, the severity and duration of the evolving COVID-19 pandemic and the resulting impact on macro-economic conditions; inconclusive clinical trial results or clinical trials failing to achieve one or more endpoints; early data not being repeated in ongoing or future clinical trials; failures to secure required regulatory approvals; disruptions from failures by third-parties on whom we rely in connection with our clinical trials; delays or negative determinations by regulatory authorities; changes or increases in oversight and regulation; increased competition; manufacturing delays or problems; inability to achieve enrollment targets; disagreements with our collaboration partners or failures of collaboration partners to pursue product candidates; legal challenges, including product liability claims or intellectual property disputes; commercialization factors, including regulatory approval and pricing determinations; disruptions to access to raw materials or starting material; delays or disruptions at our in-house manufacturing facilities; proliferation and continuous evolution of new technologies; disruptions to Calyxt's business, including disruptions resulting from Calyxt's execution of its business model; management changes; dislocations in the capital markets; and other important factors described under "Risk Factors" and "Special Note Regarding Forward-Looking Statements" in our Annual Report on Form 20-F filed with the Securities and Exchange Commission on March 4, 2021 (the "Annual Report") under "Risk Factors" in the interim reports that we file with the Securities and Exchange Commission (the "SEC") and other factors that we disclose in filings with the SEC from time to time. As a result of these factors, we cannot assure you that the forward-looking statements in this interim report will prove to be accurate. Furthermore, if our forward-looking statements prove to be inaccurate, the inaccuracy may be material. In light of the significant uncertainties in these forward-looking statements, you should not regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified time frame or at all. We undertake no obligation to publicly update any forward- looking statements, whether as a result of new information, future events or otherwise, except as required by law.

We own various trademark registrations and applications, and unregistered trademarks and service marks, including Cellectis®, TALEN® and our corporate logos, and all such trademarks and service marks appearing in this interim report are the property of Cellectis. The trademarks Calyxt®, PlantSpringTM and BioFactoryTM are owned by Calyxt. All other trade names, trademarks and service marks of other companies appearing in this interim report are the property of their respective holders. Solely for convenience, the trademarks and trade names in this interim report may be referred to without the ® and ™ symbols, but such references, or the failure of such symbols to appear, should not be construed as any indication that their respective owners will not assert, to the fullest extent under applicable law, their rights thereto. We do not intend to use or display other companies' trademarks and trade names to imply a relationship with, or endorsement or sponsorship of us by, any other companies.

As used in this interim report, the terms "Cellectis," "we," "our," "us," and "the Company" refer to Cellectis S.A. and its subsidiaries, taken as a whole, unless the context otherwise requires. References to "Calyxt" refer to Calyxt, Inc. and its subsidiaries, taken as a whole.

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