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CORRESP
 1
 filename1.htm

 CORRESP

 Cellectis S.A.
 8, rue de la Croix Jarry 75013
Paris, France July 9, 2025 VIA
EDGAR United States Securities and Exchange Commission
 Division of Corporation Finance Office of Life Sciences
 100 F Street, N.E. Washington, D.C. 20549
 Attention: Tyler Howes

 RE:
 Cellectis S.A.
 Registration Statement on Form F-3 (File
 No. 333-288491) Dear Mr. Howes:
 In accordance with Rules 460 and 461 under the Securities Act of 1933, as amended, Cellectis S.A. (the “ Registrant” ) hereby
requests that the Securities and Exchange Commission (the “ Commission” ) take appropriate action to cause the above-referenced Registration Statement on Form F-3 to become effective on
July 11, 2025 at 4:00 p.m., Eastern Time, or as soon thereafter as is practicable. The Registrant also hereby requests that the
Commission notify Peter Devlin of Jones Day at 212-326-3978 or pdevlin@jonesday.com to confirm that the Registration Statement has become effective.
 Please contact Peter Devlin of Jones Day if you have any questions concerning the foregoing. Thank you for your attention to this matter.

 Very truly yours,

 CELLECTIS S.A.

 By:

 /s/ Andre Choulika

 Name: Andre Choulika

 Title:  Chief Executive Officer

 cc:
 Peter Devlin, Jones Day

<DOCUMENT>
<TYPE>TEXT-EXTRACT
<SEQUENCE>2
<FILENAME>filename2.txt
<TEXT>
 July 7, 2025

Andr Choulika
Chief Executive Officer
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France

 Re: Cellectis S.A.
 Registration Statement on Form F-3
 Filed July 2, 2025
 File No. 333-288491
Dear Andr Choulika:

 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 Tyler Howes at 202-551-3370 with any questions.

 Sincerely,

 Division of
Corporation Finance
 Office of Life
Sciences
cc: Peter E. Devlin, Esq.
</TEXT>
</DOCUMENT>

CORRESP
1
filename1.htm

CORRESP

 Cellectis S.A.

8, rue de la Croix Jarry

 75013
Paris, France

 January 21, 2025

VIA EDGAR

 United States Securities and Exchange
Commission

 Division of Corporation Finance

 Office of Life
Sciences

 100 F Street, N.E.

 Washington, D.C. 20549

Attention:
  Jason Drory

RE:
 Cellectis S.A.

Registration Statement on Form F-3 (File
No. 333-284302)

 Dear Mr. Drory:

In accordance with Rules 460 and 461 under the Securities Act of 1933, as amended, Cellectis S.A. (the “Registrant”) hereby
requests that the Securities and Exchange Commission (the “Commission”) take appropriate action to cause the above-referenced Registration Statement on Form F-3 to become effective on
January 23, 2025 at 4:30 p.m., Eastern Time, or as soon thereafter as is practicable.

 The Registrant also hereby requests that the
Commission notify Peter Devlin of Jones Day at 212-326-3978 or pdevlin@jonesday.com to confirm that the Registration Statement has become effective.

Please contact Peter Devlin of Jones Day if you have any questions concerning the foregoing. Thank you for your attention to this matter.

Very truly yours,

CELLECTIS S.A.

By:

/s/ André Choulika

Name: André Choulika

Title:  Chief Executive Officer

cc:
 Peter Devlin, Jones Day

January 16, 2025
André Choulika
Chief Executive Officer
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France
Re:Cellectis S.A.
Registration Statement on Form F-3
Filed January 15, 2025
File No. 333-284302
Dear André Choulika:
            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 Jason Drory at 202-551-8342 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:Peter E. Devlin

CORRESP
1
filename1.htm

CORRESP

 Cellectis S.A.

8, rue de la Croix Jarry

 75013
Paris, France

 July 5, 2022

 VIA
EDGAR

 United States Securities and Exchange Commission

Division of Corporation Finance

 100 F Street, N.E.

Washington, D.C. 20549

Attention:        Mr. Gary Guttenberg

RE:
 Cellectis S.A.

Registration Statement on Form F-3 (File
No. 333-265826)

 Ladies and Gentlemen:

In accordance with Rules 460 and 461 under the Securities Act of 1933, as amended, Cellectis S.A. (the “Registrant”) hereby
requests that the Securities and Exchange Commission (the “Commission”) take appropriate action to cause the above-referenced Registration Statement on Form F-3 to become effective on
July 7, 2022 at 4:30 p.m., Eastern Time, or as soon thereafter as is practicable. The Registrant also hereby requests a copy of the written order verifying the effective date.

Please contact Peter Devlin of Jones Day at (212) 326-3978 if you have any questions concerning the
foregoing. Thank you for your attention to this matter.

Very truly yours,

CELLECTIS S.A.

By:

 /s/ André Choulika

André Choulika

Chief Executive Officer

cc:
 Peter Devlin, Jones Day

United States securities and exchange commission logo
June 29, 2022
André Choulika
Chief Executive Officer and Director
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France
Re:Cellectis S.A.
Registration Statement on Form F-3
Filed June 24, 2022
File No. 333-265826
Dear Dr. Choulika:
            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 Gary Guttenberg at (202) 551-6477 with any questions.
Sincerely,
Division of Corporation Finance
Office of Life Sciences
cc:       Peter Devlin

November 28, 2017
Marie-Bleuenn Terrier
General Counsel
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France
Cellectis S.A.
Form 20-F for the Fiscal Year Ended December 31, 2016
Filed March 23, 2017
File No. 001-36891Re:
Dear Ms. Terrier:
            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 by the staff.
Division of Corporation Finance
Office of Healthcare & Insurance

CORRESP
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CORRESP

 Cellectis S.A.

8, rue de la Croix Jarry

 75013 Paris, France

 November 14, 2017

Correspondence Filing via EDGAR Submission

Mr. Chris Edwards

 Ms. Erin Jaskot

Office of Healthcare & Insurance

 Division of
Corporation Finance

 U.S. Securities and Exchange Commission

100 F Street, N.E.

 Washington, D.C. 20549

Re:
Cellectis S.A.

Form 20-F for Fiscal Year Ended December 31, 2016

Filed March 23, 2017

File No. 001-36891

 Dear Mr. Edwards and
Ms. Jaskot:

 On behalf of Cellectis S.A. (the “Company”), I submit the Company’s response to the comment contained in the letter
of the Staff (the “Staff”) of the U.S. Securities and Exchange Commission (the “Commission”) dated October 31, 2017 relating to the Company’s aforementioned Form
20-F. For ease of reference, the text of the Staff’s comment is also set forth below (in bold) in its entirety, with the Company’s response following such text.

Form 20-F for the Fiscal Year Ended December 31, 2016

Current Intellectual Property Portfolio, page 76

1.
We refer to your proposed disclosure in response to comment 1, and note that issued patents relating to your gene-editing platform and T-cell and CAR technology platforms have
upcoming expiration dates in 2019. In future filings, please also discuss whether you expect the expiration of these patents to have a material effect on your business, including any impact on future operations and the financial position of the
company.

 Response: The Company acknowledges the Staff’s comment in response to the Company’s previously proposed
disclosure. In future filings, the Company will enhance its disclosure to discuss whether the expiration of its patents in 2019, or within one year of future filings, would have a material effect on the Company’s business, including any impact
on its future operations and financial position.

 The Company’s proposed disclosure appears in Annex A hereto, marked to show
changes from the proposal included with its previous submission.

 * * * *

 If you have any questions in connection with the foregoing, please contact me by telephone at +33 (0)7 76 98 70
74 or by e-mail at marie-bleuenn.terrier@cellectis.com.

 Very truly yours,

Cellectis S.A.

By:

/s/ Marie-Bleuenn Terrier

 Marie-Bleuenn Terrier

 General
Counsel

cc:
André Choulika

Chief Executive Officer, Cellectis S.A.

 Boris Dolgonos

Jones Day

 ANNEX A

Current Intellectual Property Portfolio

As a result of the licensing opportunities described below and our continuing research and development efforts, our intellectual property
estate now contains patent applications that cover our products, including claims that cover:

•

methods central to genome engineering and gene editing, including methods of homologous recombination, nuclease-based gene targeting, replacement, insertions and/or knock-out;

•

the main products we use in the manufacturing process, including nucleases;

•

manufacturing steps, including cell electroporation, transformation and genetic modifications;

•

engineered cells;

•

single-chain and multi-subunit CARs expressed at the surface of T-cells;

•

specific gene inactivation and suicide gene expression;

•

allogeneic and autologous treatment strategies using our T-cell products; and

•

plant traits and methods for gene editing plant cells.

 The issued patents in our portfolio
consist of approximately 26 Cellectis-owned and 46 in-licensed U.S. patents, 14 Cellectis-owned and 11 in-licensed European patents, and 45 Cellectis-owned and 11 in-licensed patents in other jurisdictions, including Australia, Canada, China, Hong Kong, India, Israel, Japan, Korea, Mexico and Singapore.

The pending patent applications in our portfolio consist of approximately 73 Cellectis-owned and 18 in licensed U.S. patent applications, 48
Cellectis-owned and 20 in-licensed European patent applications, and 322 Cellectis-owned and 70 in-licensed patent applications pending in other jurisdictions, including
Australia, Brazil, Canada, China, Hong Kong, India, Israel, Japan, Korea, Mexico and Singapore.

 Our portfolio includes a total of 144
owned and in-licensed granted patents, and 551 owned and in licensed patent applications.

 Our
UCART product candidates rely for each product candidate upon one or more patent rights protecting various aspects of the technologies, including rights relating to:

•

the genetic editing of T-cells, using TALEN technology or meganuclease technology, covered by approximately twelve Cellectis-owned patent families and three in-licensed patent families;

•

the insertion of transgenes into T-cells using electroporation of mRNA, covered by approximately five Cellectis-owned patent families;

•

the appending of attributes to T-cells, covered by approximately eight Cellectis-owned patent families and one in-licensed patent family;

•

the molecular structure of CARs, covered by approximately six Cellectis-owned patent families; and

•

specific CARs that target selected antigen markers are covered by approximately fifteen Cellectis-owned patent applications and one in-licensed patent family.

For additional information, see “—Gene-Editing Platform” below.

Similarly, our most advanced plant product candidates each rely upon one or more patent rights relating to:

•

the genetic editing of plants using TALEN technology, covered by approximately six Cellectis-owned patent families and two in-licensed patent families;

•

the genetic editing of plants using meganuclease technology, covered by approximately eight Cellectis-owned patent families and one in-licensed patent family;

•

the genetic editing of plants using CRISPR-Cas9 technology, covered by approximately two Cellectis-owned patent families and three in-licensed patent families; and

•

specific plant traits, which are covered by approximately twelve Cellectis-owned patent families.

Individual patent terms extend for varying periods of time, depending upon the date of filing of the patent application, the date of patent
issuance, and the legal term of patents in the countries in which they are obtained. In most countries in which we file patent applications, including the United States, the patent term is 20 years from the date of filing of the first non-provisional application to which priority is claimed. In certain instances, a patent term can be extended under certain circumstances. For example, in the United States, the term of a patent that covers an FDA-approved drug may be eligible for a patent term restoration of up to five years to effectively compensate for the patent term lost during the FDA regulatory review process, subject to several limitations
discussed below under “—Our Intellectual Property Strategy.” Also, in the United States, a patent’s term may be lengthened by patent term adjustment, which compensates a patentee for administrative delays by the U.S. Patent and
Trademark Office in granting a patent, or may be shortened if a patent is terminally disclaimed over an earlier-filed patent. Our issued patents will expire on dates ranging from 2019 to 2035. If patents are issued on our pending patent
applications, the resulting patents are projected to expire on dates ranging from 2023 to 2035. However, the actual protection afforded by a patent varies on a
product-by-product basis, from country-to-country, and depends upon many factors,
including the type of patent, the scope of its coverage, the availability of regulatory-related extensions, the availability of legal remedies in a particular country, and the validity and enforceability of the patent.

The patent portfolios for our most advanced product candidates, UCART 19 and UCART123, are summarized below.

Gene-Editing Platform

 Each of our UCART
product candidates relies upon our gene-editing platform and T-cell and CAR technology platforms. The patent portfolio covering these platforms and technologies, includes approximately 30 issued patents or
pending patent applications. These issued patents and pending patent applications, which expire between 2019 and 2033, cover product claims or process claims relevant to each of our product candidates, including UCART19 and UCART123.

 Our gene-editing platform and each of our
UCART product candidates benefits from the protections of several patents and patent applications in our patent portfolio. As a result of this broad range of patent protection, very few individual patents in our portfolio are critical to our ability
to effectively conduct our product development activities. Although certain patents relating to our electroporation technology will expire in 2019, other patents covering this technology remain in force, or are expected to be granted under patent
applications, and additional patents protect the nucleases delivered by our electroporation technology, as well as the methods to modify the cells by use of such nucleases. As a result of the breadth of our patent protection and the integration of
patented technologies, compositions and methods of use within our gene-editing and T-cell and CAR technology platforms, we do not expect that the expiration of these patents in 2019, individually or in the
aggregate, will have a material effect on our future operations or financial position.

 UCART19

In addition to the patent portfolio relating to our platform and technologies, described above, our patent portfolio relating specifically to
UCART19 includes pending patent applications from the patent family WO2014184143 (CD19 Specific Chimeric Antigen Receptor and Uses Thereof). We believe these pending patent applications, which, if issued, would expire in 2034, include claims to
cover the composition of matter of UCART19, methods of manufacture of UCART19, and methods to use UCART19 in treatment.

 UCART123

In addition to the patent portfolio relating to our platform and technologies, described above, our patent portfolio relating specifically to
UCART123 includes pending patent applications from the patent family WO2015140268 (CD123 Specific Chimeric Antigen Receptors for Cancer Immunotherapy). We believe these pending patent applications, which, if issued, would expire in 2034, include
claims to cover the composition of matter of UCART123, methods of manufacture of UCART123, and methods to use UCART123 in treatment.

 In
each case, some of the issued patents and pending patent applications, if issued, may be eligible for patent term extension and patent term adjustment, thereby extending their terms, as described above.

October 31, 2017
Marie-Bleuenn Terrier
General Counsel
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France
Re:Cellectis S.A.
Form 20-F for the Fiscal Year Ended December 31, 2016
Filed March 23, 2017
File No. 001-36891
Dear Ms. Terrier:
            We have reviewed your October 10, 2017 response to our comment letter and have the
following comment.
            Please respond to the comment within ten business days by providing the requested
information or advise us as soon as possible when you will respond.  If you do not believe our
comment applies to your facts and circumstances, please tell us why in your response.
            After reviewing your response to the comment, we may have additional comments.
Form 20-F for the Fiscal Year Ended December 31, 2016
Current Intellectual Property Portfolio, page 76
1.We refer to your proposed disclosure in response to comment 1, and note that issued
patents relating to your gene-editing platform and T-cell and CAR technology
platforms have upcoming expiration dates in 2019.  In future filings, please also discuss
whether you expect the expiration of these patents to have a material effect on your
business, including any impact on future operations and the financial position of the
company.

 FirstName LastNameMarie-Bleuenn Terrier
 Comapany NameCellectis S.A.
 June 16, 2017 Page 2
 FirstName LastName
Marie-Bleuenn Terrier
Cellectis S.A.
October 31, 2017
Page 2

            Please contact Chris Edwards at (202) 551-6761 or Erin Jaskot at (202) 551-3442 with
any questions.
Division of Corporation Finance
Office of Healthcare & Insurance

CORRESP
1
filename1.htm

Correspondence Letter

 Cellectis S.A.

 8, rue de la Croix
Jarry

 75013 Paris, France

 October 10, 2017

Correspondence Filing via EDGAR Submission

Mr. Chris Edwards

 Ms. Erin Jaskot

Office of Healthcare & Insurance

 Division of
Corporation Finance

 U.S. Securities and Exchange Commission

100 F Street, N.E.

 Washington, D.C. 20549

Re:
Cellectis S.A.

 Form 20-F for Fiscal Year Ended December 31, 2016

Filed March 23, 2017

File No. 001-36891

 Dear
Mr. Edwards and Ms. Jaskot:

 On behalf of Cellectis S.A. (the “Company”), I submit the Company’s response to the comment
contained in the letter of the Staff (the “Staff”) of the U.S. Securities and Exchange Commission (the “Commission”) dated September 12, 2017 relating to the Company’s aforementioned Form 20-F. For ease of
reference, the text of the Staff’s comment is also set forth below (in bold) in its entirety, with the Company’s response following such text.

Form 20-F

 Current Intellectual Property Portfolio,
page 76

1.
In future filings, for each of your material product candidates, please expand your disclosure to discuss the type of patent protection you have (e.g., composition of matter, use or process) and the expiration (or
expected expiration) dates of the most significant patents within the portfolio. Please ensure that your disclosure specifically addresses the patent expiration dates for any patents related to UCART19 and UCART123.

Response: The Company acknowledges the Staff’s comment. In future filings, the Company will expand its disclosure to discuss the type of patent
protection that the Company has and the expiration, or expected expiration, dates of the most significant patents within the portfolio, including UCART19 and UCART123.

The Company’s proposed disclosure based on its Form 20-F for the fiscal year ended December 31, 2016, is presented in
Annex A hereto, with the additional language underlined and deletions struck through.

 * * * *

 If you
have any questions in connection with the foregoing, please contact me by telephone at +33 (0)7 76 98 70 74 or by e-mail at marie-bleuenn.terrier@cellectis.com.

Very truly yours,

Cellectis S.A.

By:

/s/ Marie-Bleuenn Terrier

Marie-Bleuenn Terrier

General Counsel

cc:
André Choulika

 Chief Executive Officer, Cellectis S.A.

Boris Dolgonos

 Jones Day

 ANNEX A

Current Intellectual Property Portfolio

As a result of the licensing opportunities described below and our continuing research and development efforts, our intellectual property
estate now contains patent applications that cover our products, including claims that cover:

•

methods central to genome engineering and gene editing, including methods of homologous recombination, nuclease-based gene targeting, replacement, insertions and/or knock-out;

•

the main products we use in the manufacturing process, including nucleases;

•

manufacturing steps, including cell electroporation, transformation and genetic modifications;

•

engineered cells;

•

plant traits and methods for gene editing plant cells;

•

single-chain and multi-subunit CARs expressed at the surface of T-cells;

•

specific gene inactivation and suicide gene expression; and

•

allogeneic and autologous treatment strategies using our T-cell products.; and

•

plant traits and methods for gene editing plant cells.

 The issued patents in our
portfolio consist of approximately 26 Cellectis-owned and 46 in-licensed U.S. patents, 14 Cellectis-owned and 11 in-licensed European patents, and 45 Cellectis-owned and 11 in-licensed patents in other jurisdictions, including Australia,
Canada, China, Hong Kong, India, Israel, Japan, Korea, Mexico and Singapore.

 The pending patent applications in our portfolio consist of
approximately 73 Cellectis-owned and 18 in licensed U.S. patent applications, 48 Cellectis-owned and 20 in-licensed European patent applications, and 322 Cellectis-owned and 70 in-licensed patent applications pending in other jurisdictions,
including Australia, Brazil, Canada, China, Hong Kong, India, Israel, Japan, Korea, Mexico and Singapore.

 Our portfolio includes a total
of 144 owned and in-licensed granted patents, and 551 owned and in licensed patent applications.

 Our UCART product candidates rely for
each product candidate upon one or more patent rights protecting various aspects of the technologies, including rights relating to:

•

the genetic editing of T-cells, using TALEN technology or meganuclease technology, covered by approximately twelve Cellectis-owned patent families and three in-licensed patent families;

•

the insertion of transgenes into T-cells using electroporation of mRNA, covered by approximately five Cellectis-owned patent families;

•

the appending of attributes to T-cells, covered by approximately eight Cellectis-owned patent families and one in-licensed patent family;

•

the molecular structure of CARs, covered by approximately six Cellectis-owned patent families; and

•

specific CARs that target selected antigen markers are covered by approximately fifteen Cellectis-owned patent applications and one in-licensed patent family.

For additional information, see “—Gene-Editing Platform” below.

Similarly, our most advanced plant product candidates each rely upon one or more patent rights relating to:

•

the genetic editing of plants using TALEN technology, covered by approximately six Cellectis-owned patent families and two in-licensed patent families;

•

the genetic editing of plants using meganuclease technology, covered by approximately eight Cellectis-owned patent families and one in-licensed patent family;

•

the genetic editing of plants using CRISPR-Cas9 technology, covered by approximately two Cellectis-owned patent families and three in-licensed patent families; and

•

specific plant traits, which are covered by approximately twelve Cellectis-owned patent families.

Individual patent terms extend for varying periods of time, depending upon the date of filing of the patent application, the date of patent
issuance, and the legal term of patents in the countries in which they are obtained. In most countries in which we file patent applications, including the United States, the patent term is 20 years from the date of filing of the first
non-provisional application to which priority is claimed. In certain instances, a patent term can be extended under certain circumstances. For example, in the United States, the term of a patent that covers an FDA-approved drug may be eligible for a
patent term restoration of up to five years to effectively compensate for the patent term lost during the FDA regulatory review process, subject to several limitations discussed below under “—Our Intellectual Property Strategy.” Also,
in the United States, a patent’s term may be lengthened by patent term adjustment, which compensates a patentee for administrative delays by the U.S. Patent and Trademark Office in granting a patent, or may be shortened if a patent is
terminally disclaimed over an earlier-filed patent. Our issued patents will expire on dates ranging from 2015 2019 to 2035. If patents are issued on our pending patent applications, the resulting patents are projected to
expire on dates ranging from 2023 to 2035. However, the actual protection afforded by a patent varies on a product-by-product basis, from country-to-country, and depends upon many factors, including the type of patent, the scope of its coverage, the
availability of regulatory-related extensions, the availability of legal remedies in a particular country, and the validity and enforceability of the patent.

The patent portfolios for our most advanced product candidates, UCART 19 and UCART123, are summarized below.

Gene-Editing Platform

 Each
of our UCART product candidates relies upon our gene-editing platform and T-cell and CAR technology platforms. The patent portfolio covering these platforms and technologies, includes approximately 30 issued patents or pending patent
applications. These issued patents and pending patent applications, which expire between 2019 and 2033, cover product claims or process claims relevant to each of our product candidates, including UCART19 and UCART123.

 UCART19

In addition to the patent portfolio relating to our platform and technologies, described above, our patent portfolio relating specifically
to UCART19 includes pending patent applications from the patent family WO2014184143 (CD19 Specific Chimeric Antigen Receptor and Uses Thereof). We believe these pending patent applications, which, if issued, would expire in 2034, include claims to
cover the composition of matter of UCART19, methods of manufacture of UCART19, and methods to use UCART19 in treatment.

 UCART123

In addition to the patent portfolio relating to our platform and technologies, described above, our patent portfolio relating specifically
to UCART123 includes pending patent applications from the patent family WO2015140268 (CD123 Specific Chimeric Antigen Receptors for Cancer Immunotherapy). We believe these pending patent applications, which, if issued, would expire in 2034, include
claims to cover the composition of matter of UCART123, methods of manufacture of UCART123, and methods to use UCART123 in treatment.

In each case, some of the issued patents and pending patent applications, if issued, may be eligible for patent term extension and patent
term adjustment, thereby extending their terms, as described above.

CORRESP
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filename1.htm

Correspondence letter

 Cellectis S.A.

 8, rue de la Croix
Jarry

 75013 Paris, France

 September 25, 2017

Correspondence Filing via EDGAR Submission

Mr. Chris Edwards

 Ms. Erin Jaskot

Office of Healthcare & Insurance

 Division of
Corporation Finance

 U.S. Securities and Exchange Commission

100 F Street, N.E.

 Washington, D.C. 20549

Re:
Cellectis S.A.

Form 20-F for Fiscal Year Ended December 31, 2016

Filed March 23, 2017

File No. 001-36891

 Dear Mr. Edwards and Ms. Jaskot:

On behalf of Cellectis S.A. (the “Company”), I acknowledge that the Company has received the letter of the Staff (the
“Staff”) of the U.S. Securities and Exchange Commission dated September 12, 2017 relating to the Company’s aforementioned Form 20-F, which requested that the Company respond to the Staff’s comment within ten business
days.

 On September 22, 2017, Boris Dolgonos of Jones Day, the Company’s outside counsel, contacted the Staff on behalf of the Company to
request that the Company be provided with additional time to respond to the Staff’s comment. Mr. Dolgonos has informed me that the Staff agreed to accommodate the Company’s request and provided an extension through October 10,
2017.

 On behalf of the Company, I confirm that the Company will submit its response to the Staff’s comment no later than October 10, 2017.

* * * *

 If you have any questions in connection with the
foregoing, please contact me by telephone at +33 (0)7 76 98 70 74 or by e-mail at marie-bleuenn.terrier@cellectis.com.

 Very truly yours,

Cellectis S.A.

By:

/s/ Marie-Bleuenn Terrier

Marie-Bleuenn Terrier

General Counsel

cc:
André Choulika

 Chief Executive Officer, Cellectis S.A.

Boris Dolgonos

 Jones Day

September 12, 2017
Marie-Bleuenn Terrier
General Counsel
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France
Cellectis S.A.
Form 20-F for Fiscal Year Ended December 31, 2016
Filed March 23, 2017
File No. 001-36891Re:
Dear Ms. Terrier:
We have reviewed your filing and have the following comment.
Please respond to the comment within ten business days by providing the requested
information or advise us as soon as possible when you will respond.  If you do not believe our
comment applies to your facts and circumstances, please tell us why in your response.
After reviewing your response to the comment, we may have additional comments.
Form 20-F
Current Intellectual Property Portfolio, page 76
1. In future filings, for each of your material product candidates, please expand your
disclosure to discuss the type of patent protection you have (e.g., composition of matter,
use or process) and the expiration (or expected expiration) dates of the most significant
patents within the portfolio.  Please ensure that your disclosure specifically addresses the
patent expiration dates for any patents related to UCART19 and UCART123.
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.

Marie-Bleuenn Terrier
Cellectis S.A.
September 12, 2017
Page 2

Please contact Chris Edwards at (202) 551-6761 or Erin Jaskot at (202) 551-3442 with
any questions.
Division of Corporation Finance
Office of Healthcare & Insurance

CORRESP
1
filename1.htm

CORRESP

 Cellectis S.A.

8, rue de la Croix Jarry

 75013
Paris, France

 April 14, 2017

VIA EDGAR

 United States Securities and Exchange
Commission

 Division of Corporation Finance

 100 F Street,
N.E.

 Washington, D.C. 20549

Attention:

 Ms. Suzanne Hayes

 Ms. Mary Beth Breslin

 Ms. Ada D. Sarmento

RE:
Cellectis S.A.

 Registration Statement on Form
F-3 (File No. 333-217086)

 Ladies and Gentlemen:

In accordance with Rules 460 and 461 under the Securities Act of 1933, as amended, Cellectis S.A. (the “Registrant”) hereby
requests that the Securities and Exchange Commission (the “Commission”) take appropriate action to cause the above-referenced Registration Statement on Form F-3 to become effective on
April 19, 2017 at 4:00 p.m., Eastern Time, or as soon thereafter as is practicable. The Registrant also hereby requests a copy of the written order verifying the effective date.

Please contact Boris Dolgonos of Jones Day at (212) 326-3430 if you have any questions concerning the
foregoing. Thank you for your attention to this matter.

Very truly yours,

CELLECTIS S.A.

By:

 /s/ André Choulika

André Choulika

Chief Executive Officer

cc:
Boris Dolgonos, Jones Day

Mail Stop 4546
April 7 , 2017

André Choulika
Chief Executive Officer
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France

Re: Cellectis S.A.
  Registration Statement on Form F-3
Filed  March 31, 2017
  File No.  333-217086

Dear Mr. Choulika :

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 Ada D. Sarmento at (202) 551 -3798  with any questions.

Sincerely,

 /s/ Mary Beth Breslin for

Suzanne Hayes
Assistant Director
Office of Healthcare and Insurance

cc:  Boris Dolgonos
 Jones Day

CORRESP
1
filename1.htm

Correspondence

 Cellectis S.A.

8, rue de la Croix Jarry

 75013
Paris, France

 March 23, 2015

VIA EDGAR

 United States Securities and Exchange
Commission

 Division of Corporation Finance

 100 F Street,
N.E.

 Washington, D.C. 20549

Attention:
Mr. Jeffrey P. Riedler

 Mr. Johnny Gharib

Mr. Bryan Pitko

RE:
Cellectis S.A.

 Registration Statement on Form F-1 (File No. 333-202205)

 Ladies and Gentlemen:

 In accordance with
Rule 461 under the Securities Act of 1933, as amended, Cellectis S.A. (the “Registrant”) hereby requests that the Securities and Exchange Commission (the “Commission”) take appropriate action to cause the
above-referenced Registration Statement on Form F-1 to become effective on March 24, 2015 at 4:00 p.m., Eastern Time, or as soon thereafter as is practicable. The Registrant hereby authorizes Boris Dolgonos, an attorney with our legal counsel,
Jones Day, to orally modify or withdraw this request for acceleration. The Registrant also hereby requests a copy of the written order verifying the effective date.

In connection with this request, the Registrant acknowledges that:

•

should the Commission or the staff of the Commission (the “Staff”), acting pursuant to delegated authority, declare the filing effective, it does not foreclose the Commission from taking any action with
respect to the filing;

•

the action of the Commission or the Staff, acting pursuant to delegated authority, in declaring the filing effective, does not relieve the Registrant from its full responsibility for the adequacy and accuracy of the
disclosure in the filing; and

•

the Registrant may not assert Staff comments and the declaration of effectiveness as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.

 Please contact Boris Dolgonos of Jones Day at (212) 326-3430 if you have any questions
concerning the foregoing. Thank you for your attention to this matter.

Very truly yours,

CELLECTIS S.A.

By:

 /s/ André Choulika

André Choulika

Chief Executive Officer

cc:
Boris Dolgonos, Jones Day

February 9 , 2015

Via E -mail
Andre Choulika
Chief Executive Officer
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France

Re: Cellectis S.A.
Amendment No. 1 to Draft Registration  Statement on Form F -1
Submitted January 27, 2015
  CIK No. 0001627281

Dear Mr. Choulika:

We have reviewed amendment no. 1 to your draft registration statement and have the
following comments.  In some of our comments, we may ask you to provide us with information
so we may better understand your disclosure.

Please respond to this letter by providing the requested information and either submitting
an amended draft registration statement or publicly filing your registration statement on
EDGAR.  If you do  not believe our comments apply to your facts and circumstances or do not
believe an amendment is appropriate, please tell us why in your response.

After reviewing the information you provide in response to these comments and your
amended draft registra tion statement or filed registration statement, we may have additional
comments.

Overview, page 1

1. We note your response to comment 1 and your continued disclosure that “[r]ecent clinical
results indicate that CAR -based immunotherapy is one of the most promising areas of
cancer research…”  As you have not yet commenced any clinical trials with respect to
CAR -based immunotherapy, please expand your disclosure to describe the clinical results
you are referring to, including the subject of the trials, who a nd when they were
conducted and why you believe they suggest that CAR -based immunotherapy is a
“promising area of cancer research.”

The rights of shareholders in companies subject to French corporate law differ, page 66

2. We reissue comment 12.   Please in clude a relevant discussion under this heading or in a
separate risk factor.

Andre Choulika
Cellectis S.A.
February 9 , 2015
Page 2

 Use of Proceeds, page 71

3. We note your responses to our prior comment 13 and 14 that you are not able to provide
the information requested by our comment.  Item 504 of Regulatio n S-K requires
disclosure of the approximate amount intended to be used for each specific purposes
identified for the use of proceeds.  We understand that the development of product
candidates is subject to uncertainty, but that does not relieve you of you r obligation to
provide investors with your best estimate, based on reasonable assumptions, of the
manner in which you will allocate investors’ funds.  In this regard, we note that your
pipeline table identifies four UCART product candidates at various sta ges of
development that you expect to enter into clinical or pre -clinical studies in 2015.  Your
use of proceeds disclosure should indicate how you expect to prioritize the use of
proceeds from the offering to advance each of the product candidates in this  regard.
Accordingly, please revise your use of proceeds disclosure to  indicate :

 how you intend to allocate the proceeds of the offering towards the development of
each of your product candidates; and

 how far in the pre -clinical and/or clinical d evelopment process you expect the
allocated proceeds from this offering will enable you to reach for each of the product
candidates you identify.

Management’s Discussion and Analysis of Financial Condition and Results of Operations
Overview, page 79

4. Please refer to your response to comment 15. You state that the company considers
payments from Servier and Pfizer to be cash generated by operations.  However, on page
80 you disclose that “payments under our strategic alliances” is another source of fund ing
in addition to cash generated by operations.  Therefore please revise your disclosure to be
consistent with page 91 or explain to us why “cash generated by operations” is not a
duplicative explanation.

Financial Operations Overview
Research and Devel opment Expenses, page 83

5. Please refer to your response to comment 16.  You state that you do not track research
and development expenses by product candidate.  However, our comment had asked for
disclosure of external costs since you disclose on page 83 t hat you track significant
external costs by product candidate.  Therefore, please clarify your disclosure on page 83
to clarify that you do not track any research and development expenses by product, if
true, or alternatively provide the disclosure request ed in our original comment.

Andre Choulika
Cellectis S.A.
February 9 , 2015
Page 3

 Intellectual Property
Current Intellectual Property Portfolio, page 123

6. We note your response to our prior comment 20 and your revised disclosure providing
the expirations dates and jurisdictions for your patents and patent ap plications.  Please
revise your disclosure to identify the specific product candidates and related technologies
covered by the patent and patent applications you identify.

Results of Operations
Research and development expenses, page 87

7. Since research and development expenses are a significant portion of your results of
operations, please provide a quantitative discussion of the nature of research and
development expenses for each period presented.

Statement of Consolidated Operations, page F -4

8. Please  refer to your response to comment 30.  Please explain to us why ‘Revenues and
other income” are not part of ‘Operating income’ since they are included in the
calculation for ‘Operating Loss’.

Notes to the Consolidated Financial Statements
Note 3. Summary  of significant accounting policies
3.19 Classification of operating expenses, page F -17

9. We acknowledge that you are still evaluating comment 31 and this comment will remain
open until you we review your response to the comment.

You may contact Vanessa Robertson at (202) 551 -3649 or Lisa Vanjoske at (202) 551 -
3614 if you have questions regarding comments on the financial statements and related matters.
Please contact Johnny Gharib at (202) 551 -3170, Bryan Pitko at (202) 551 -3203 or me at (202)
551-3715  with any other questions.

Sincerely,

 /s/ Bryan J. Pitko for

Jeffrey P. Riedler
Assistant Director

cc: Via E -mail
 Boris Dolgonos, Esq.
 Jones Day

January 15, 2015

Via E -mail
Andre Choulika
Chief Executive Officer
Cellectis S.A.
8, rue de la Croix Jarry
75013 Paris, France

Re: Cellectis S.A.
Draft Registration Statement on Form F-1
Submitted December 19, 2014
  CIK No. 0001627281

Dear Mr. Choulika:

We have reviewed your draft registration statement and have the following comments.  In
some of our comments, we may ask you to provide us with information so we may better
understand your disclosure.

Please respond to this letter by providing the requested information and either submitting
an amended draft registration statement or publicly filing your registration statement on
EDGAR.  If you do not believe our comments app ly to your facts and circumstances or do not
believe an amendment is appropriate, please tell us why in your response.

After reviewing the information you provide in response to these comments and your
amended draft registration statement or filed regis tration statement, we may have additional
comments.

Summary
Overview, page 1

1. The third sentence in this section states, “[r]ecent unprecedented clinical results indicate
that CAR -based immunotherapy is one of the most promising areas of cancer research ,
and we believe that it represents a new paradigm for cancer treatment.”  Please expand
your disclosure throughout the prospectus to describe the clinical results you are referring
to in this statement, including the subject of the trials, who and when th ey were
conducted and why the results are unprecedented.

2. Please briefly describe the novel safety and efficacy attributes that your gene -editing
expertise allows you to feature in your product candidates as discussed in the penultimate
sentence of the f irst paragraph of this section.

Andre Choulika
Cellectis S.A.
January 15, 2015
Page 2

 Our Immuno -oncology Pipeline, page 3

3. Please revise your disclosure in this section to specifically highlight that all of your
therapeutic product candidate development programs are still in the discovery or pre -
clinical pr oof-of-concept phase.

Risk Factors
Risks Related to Our Financial Condition and Capital Requirements
We may need to raise additional funding even if this offering is successful…, page 12

4. Please expand your disclosure in this risk factor to quantify the  amount of your cash and
cash equivalents.

We are limited in our ability to raise additional share capital…, page 13

5. Please revise your risk factor disclosure to identify the level of shareholder approval
required at an extraordinary meeting  to authorize an increase in the Company’s share
capital.

Risks Related to the Discovery, Development and Commercialization of Our Therapeutic
Product Candidates
Further development and commercialization of our own product candidates…, page 25

6. Please expand  your risk factor to disclose under what circumstances Servier and Pfizer
may terminate their agreements with you.

Product liability lawsuits could divert our resources, result in substantial…, page 31

7. Please quantify the amount of product liability insu rance you carry and whether the
amount of your coverage is typical for a company in your industry.  Please also provide
this information when you discuss any other types of insurance you carry.

Risks Related to Intellectual Property
If we fail to comply w ith out obligations in the agreements under which we…, page 51

8. Please delete the fourth paragraph of this risk factor as it appears to repeat the same
disclosure provided in the first half of the third paragraph.

9. Please identify the licensors which contr ol patent prosecution for your licensed
technology.

Risks Related to Our Organization, Structure and Operation
We depend on key personnel and attracting qualified management personnel…, page 53

10. Please identify the key personnel to whom you are referring in this risk factor.

Andre Choulika
Cellectis S.A.
January 15, 2015
Page 3

 Risks Related to This Offering and Ownership of Our Ordinary Shares and ADSs
As a foreign private issuer, we are permitted to adopt certain home country…, page 63

11. Please ensure that your discussion includes all of the home country corporate governance
practices that you intend to follow as disclosed under “Corporate Governance Practices”
on page 150.

The rights of shareholders in companies subject to French corporate law differ…, page 65

12. Please include a discussion of how legal fe es are or may be borne by shareholders in
derivative actions as disclosed under “Shareholder Suits” on page 181.

Use of Proceeds, page 70

13. We note that the first bullet point identifying your use of net proceeds  from the offering
indicates that you will use proceeds to dev elop your proprietary immuno -oncology
product candidates, including through pre -clinical and clinical trials.  Please revise this
disclosure to indicate  how you intend to prioritize your use of proceeds towards the
development of each of your product candid ates.  In this regard, we note that you identify
UCART19 as your most advanced product candidate and that you intend to file a CTA
application and commence enrollment of clinical trials for UCART19 in 2015.

14. Please revise your disclosure to indicate how f ar in the pre -clinical and/or clinical
development process you expect the allocated proceeds from this offering will enable you
to reach for each of the product candidates you identify.

Management’s Discussion and Analysis of Financial Condition and Results of Operations
Overview, page 78

15. You state “In addition to our cash generated by operations, we have funded our
operations…”  Please revise this disclosure as it does not appear that your operations
have generated cash or tell us why you believe no  revision is necessary.

Financial Operations Overview
Research and Development Expenses, page 82

16. Please expand your disclosures to include the total external costs incurred during each
period presented and to date for each product candidate separately or  disclose why you do
not provide such disclosure.

Results of Operations
Selling, general and administrative expenses, page 86

17. Please revise your disclosure to quantify the amount of change  due to each factor.

Andre Choulika
Cellectis S.A.
January 15, 2015
Page 4

 Business
Immunotherapy: Turning the Immune System into “Smart Drugs”
Chimeric Antigen Receptor (CARs), page 101

18. Please enlarge your diagram on page 102 so that the text in the diagram is legible.

Nuclease Technology and T -cells: The Design Process
Step 1: Add Genes, such as a CAR, page 107

19. Pleas e describe what you mean by a “viral carrier, or vector” and more specifically your
“lentiviral system” as discussed in the first paragraph of this section.

Intellectual Property
Current Intellectual Property Portfolio, page 122

20. Please revise the descri ption of your owned and in -licensed patent rights to discuss your
issued patents separately from your patent applications and identify the jurisdictions
where your patents have been issued and where your patent applications are pending.

Material Exclusive  Licenses Granted to Cellectis , page 124

21. We note that on pages 121 -122, you state that you have entered into various agreements
regarding your intellectual property; however your disclosure on pages 124 -126 only
discusses the L’Institut Pasteur, UMN and Ohio State agreements.  Please expand your
disclosure to also discuss your agreements with Precision Biosciences, Life Technologies
Corporation and University College London.  In your discussion, please include the
material terms of the agreements, including the parties’ rights and obligations, the
duration of the agreements, termination provisions and any payments required to be made
under the agreements, including upfront payments, aggregate milestones  and royalties .
Also, please file each agreement as an exhibit or provide your analysis as to wh y an
agreement is not required to be filed.

Licenses from Institut Pasteur, page 124

22. Please revise your disclosure regarding your license agreements with L’Institut Pasteur to
describe the material terms of the agreements, including whether you were gran ted an
exclusive or non -exclusive license under the second June 2000 agreement and the
October 2000 agreement, the upfront payments made under each agreement, aggregate
milestones payable under each agreement and royalties payable under each agreement.
In regard to the duration of each agreement, where such duration is conditioned on the
expiration of the last to expire patent licensed to you, please revise your disclosure to
indicate when such patents are expected to expire.

Andre Choulika
Cellectis S.A.
January 15, 2015
Page 5

 23. We note that under the first June 2000 Pasteur license agreement, exclusivity of such
license grant is subject to “certain rights” granted to third parties under the licensed
intellectual property.  Please expand your disclosure to describe these rights.

License from Regents of the University of Minnesota, page 125

24. Please revise your disclosure regarding your license agreement with UMN to describe the
material terms of the agreement, including the upfront license fee paid to UMN,
aggregate milestones payable, royalties  and the certa in patent -related expenses which you
are obligated to pay.

License from Ohio State Innovation Foundation, page 125

25. Please revise your disclosure regarding your license agreement with Ohio State to
describe the material terms of the agreement, including  the upfront license fee paid to
Ohio State, aggregate milestones payable  and royalties .  In regard to the duration of each
agreement, where such duration is conditioned on the expiration of the last to expire
patent licensed to you, please revise your dis closure to indicate when such patents are
expected to expire.  Please also file the agreement as an exhibit or provide an analysis as
to why it is not required to be filed.

License Agreement from Regents of the University of Minnesota, page 126

26. Please re vise your disclosure regarding Cellectis Plan Sciences’ license agreement with
UMN to describe the material terms of the agreement, including the upfront license fee
paid to UMN , royalties , the patent -related expenses which CPS is obligated to pay and
the aggregate amount of any milestones payable.  In regard to the duration of the
agreement, we note that the agreement will continue in effect until no licensed patent is
active and until no licensed patent application is pending.  Please expand your disclosu re
to provide the expected expiration date of such patent or patent application.  Please also
file the agreement as an exhibit or provide an analysis as to why it is not required to be
filed.

Compensation of Directors and Executive Officers, page 153

27. With your next amendment, please revise your disclosure concerning the compensation
paid to directors and executive officers to reflect information as of the end of your last
full financial year on December 31, 2014.

Other Outstanding Securities
Trout Warrant Agreement, page 164

28. Please file the Trout Warrant Agreement as an exhibit.

Andre Choulika
Cellectis S.A.
January 15, 2015
Page 6

 Enforceability of Civil Liabilities, page 209

29. If you have provided this discussion based upon an opinion of counsel, please name
counsel and file a consent to use its na me and opinion.  Please see Item 101(g)(2) of
Regulation S -K.

Statement of Consolidated Operations, page F -4

30. On page 81 you state that operating income consists of revenues and other income.
Therefore, please revise your headings in the statements of consolidated operations since
‘Operating income’ is the heading under ‘Total revenue and other income’.

Notes to the Consolidated Financial Statements
Note 3. Summary of significant accounting policies
3.19 C lassification of operating expenses, page F -17

31. Please explain to us why expenses associated with obtaining patents are classified as
selling, general and administrative expense.  Under paragraphs 126 and 127 of IAS 38,
which incorporate the guidance in paragraphs 66 and 67 of IAS 38, the costs to regi ster a
legal  right are considered development costs .

Note 5. Reportable segments, page F -19

32. On page 81 you disclose that you derive substantially all of your revenues from payments
pursuant to your collaboration agreements with Pfizer and Servier, paten t licensing
arrangements, royalties on licensed products or technologies and research and
development services. You disclose on page F -20 that revenues from external customers
by products and services for fiscal year 2012 and 2013 are given in Note 18.  Ho wever,
Note 18 only discloses total revenue by segment and the amounts disclosed can already
be found on page F -20.  Therefore, please revise your disclosures to include the amount
of revenue separately for each product and service in compliance with parag raph 32 of
IFRS 8.

33. Please expand your disclosures about major customers to include the year ended
December 31, 2013 rather than only 2012.

General

34. We note that there are a number of additional exhibits that still need to be filed.  Please
provide these exhibits as promptly as possible.  Please note that we may have comments
on these materials once they are provided.

35. Please confirm that the graphics included in your registration statement are the only
graphics you will use in your prospectus.  If those a re not the only graphics, please
provide any additional graphics prior to their use for our review.

Andre Choulika
Cellectis S.A.
January 15, 2015
Page 7

 36. Please supplementally provide us with copies of all written communications, as defined
in Rule 405 under the Securities Act, that you , or anyone authorized  to do so on your
behalf , present to potential investors in reliance on Section 5(d) of the Securities Act,
whether or not they retain copies of the communications.

If you intend to respond to these comments with an amended draft registration statement,
please submit it and any associated correspondence in accordance with the guidance we provide
in the Division’s October 11, 2012 announcement on the SEC website at
http://www.sec.gov/divisions/corpfin/cfannouncements/drsfilingprocedures101512.htm.

Please  keep in mind that we may publicly post filing review correspondence in
accordance with our December 1, 2011 policy
(http://www.sec.gov/divisions/corpfin/cfannouncements/edgarcorrespondence.htm).  If you
intend to use Rule 83 (17 CFR 200.83) to request con fidential treatment of information in the
correspondence you submit on EDGAR, please properly mark that information in each of your
confidential submissions to us so we do not repeat or refer to that information in our comment
letters to you.

You may co ntact Vanessa Robertson at (202) 551 -3649 or Lisa Vanjoske at (202) 551 -
3614 if you have questions regarding comments on the financial statements and related matters.
Please contact Johnny Gharib at (202) 551 -3170, Bryan Pitko at (202) 551 -3203 or me at (202)
551-3715 with any other questions.

Sincerely,

 /s/ Bryan J. Pitko for

Jeffrey P. Riedler
Assistant Director

cc: Via E -mail
 Boris Dolgonos, Esq.
 Jones Day