SecProbe.io

September 18, 2019
David M. Epstein
Chief Executive Officer
Black Diamond Therapeutics, Inc.
139 Main Street
Cambridge, MA 02142
Re:Black Diamond Therapeutics, Inc.
Draft Registration Statement on Form S-1
Submitted August 23, 2019
File No. 377-02808
Dear Dr. Epstein:
            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 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 registration statement or filed registration statement, we may have additional
comments.
Draft Registration Statement on Form S-1
Our pipleline, page 3
1.Please refer to the "Discovery," "Optimization" and "IND-enabling" columns.  Please
advise how "IND-enabling" differs from pre-clinical.  Additionally, please advise what is
the difference between "Discovery" and "Optimization."  To the extent you retain these
columns rather than just "Discovery" and "Pre-Clinical" columns, please add detailed
footnotes to the table to explain each development phase clearly so that investors can
appreciate the differences between the phases.

 FirstName LastNameDavid M. Epstein
 Comapany NameBlack Diamond Therapeutics, Inc.
 September 18, 2019 Page 2
 FirstName LastNameDavid M. Epstein
Black Diamond Therapeutics, Inc.
September 18, 2019
Page 2
2.For the BDTX-189 row in the pipeline table, please remove the "in progress" bar from the
Phase 1 column.  In this regard, we note you disclose that you plan to start a combined
Phase 1/2 clinical trial in the first half of 2020, which implies that Phase 1 testing has not
yet commenced for this drug candidate.  Please make a conforming revision to the
pipeline table in the business section of the prospectus.
Our BDTX-189 program, page 4
3.Please refer to the included chart.  We note your comparison to approved drugs, erlotinib
and osimertinib.  Please tell us on what basis you believe you are able to make these
comparisons given your pre-clinical stage and the lack of any head-to-head clinical trials
or, alternatively, delete these comparisons.
Implications of being an emerging growth company, page 8
4.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.
Use of proceeds, page 87
5.We note that the net proceeds will be used to fund the clinical development of BDTX-189
to include your planned Phase 1/2 clinical trial.  Please revise your disclosure to specify
how far in the clinical development you expect to reach with the net proceeds.
Critical accounting policies and significant judgments and estimates
Stock-based compensation
Determination of the fair value of common stock, page 108
6.Once you have an estimated offering price or range, please explain to us the reasons for
any differences between the recent valuations of your common stock leading up to the
initial public offering and the estimated offering price. This information will help facilitate
our review of your accounting for equity issuances including stock compensation and
beneficial conversion features.
Choice of forum, page 181
7.We note that your forum selection provision identifies the Court of Chancery of the State
of Delaware as the exclusive forum for certain litigation, including any “derivative
action.”  Please disclose whether this provision applies to actions arising under the
Securities Act.  In that regard, we note that Section 22 of the Securities Act creates
concurrent jurisdiction for federal and state courts over all suits brought to enforce any
duty or liability created by the Securities Act or the rules and regulations thereunder.  If
the provision applies to Securities Act claims, please also revise your prospectus to state

 FirstName LastNameDavid M. Epstein
 Comapany NameBlack Diamond Therapeutics, Inc.
 September 18, 2019 Page 3
 FirstName LastName
David M. Epstein
Black Diamond Therapeutics, Inc.
September 18, 2019
Page 3
that there is uncertainty as to whether a court would enforce such provision and that
investors cannot waive compliance with the federal securities laws and the rules and
regulations thereunder.  If this provision does not apply to actions arising under the
Securities Act or Exchange Act, please also ensure that the exclusive forum provision in
the governing documents states this clearly.
General
8.Please provide us mockups of any pages that include any additional pictures or graphics
to be presented, including any accompanying captions.  Please keep in mind, in
scheduling your printing and distribution of the preliminary prospectus, that we may have
comments after our review of these materials.
            You may contact Sasha Parikh at 202-551-3627 or Kevin Vaughn at 202-551-3494 if you
have questions regarding comments on the financial statements and related matters.  Please
contact Donald Field at 202-551-3680 or Dietrich King at 202-551-8071 with any other
questions.
Sincerely,
Division of Corporation Finance
Office of Healthcare & Insurance