May 23, 2019

Chad Robins
Chief Executive Officer
Adaptive Biotechnologies Corporation
1551 Eastlake Avenue East
Suite 200
Seattle, WA 98102

       Re: Adaptive Biotechnologies Corporation
           Amendment No. 1
           Draft Registration Statement on Form S-1
           Submitted May 8, 2019
           CIK No. 0001478320

Dear Mr. Robins:

      We have reviewed your amended 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.

Amendment No. 1 to Draft Registration Statement on Form S-1

Overview, page 3

1.     We note your response to comment 4. Please expand your disclosure to
include yourtime
       horizon for expected discussions with the FDA and IND submissions for
your TCR-based
       cellular therapy product candidates.
 Chad Robins
FirstName LastNameChadCorporation
Adaptive Biotechnologies Robins
Comapany NameAdaptive Biotechnologies Corporation
May 23, 2019
May 23, 2019 Page 2
Page 2
FirstName LastName
Management's Discussion and Analysis of Financial Condition and Results of
Operations
Comparison of the Years Ended December 31, 2017 and 2018
Research and Development, page 93

2.       We have reviewed your response and revised disclosure in response to
our prior comment
         10. While you do not track R&D costs by product candidate it appears
that you do track
         such costs by other classifications, including personnel costs, rent,
software development
         costs and depreciation expense. Please revise to disclose the costs
incurred by the types of
         costs classified as research and development for each period
presented.
Our Market, page 105

3.       We note your response to comment 2. Please balance your disclosure in
this section by
         clarifying that the total potential addressable market information is
based on a number of
         estimates and assumptions and that for the largest portion of the
potential addressable
         market, drug discovery, you are still in the very early stages of
developing product
         candidates.
Exclusive Forum, page 176

4.       We note your response to comment 7. Please revise your disclosure to
clarify that your
         stockholders will not be deemed to have waived your compliance with
the federal
         securities laws and the rules and regulations thereunder.
Consolidated Financial Statements
Notes to Financial Statements
Microsoft Collaboration Agreement, page F-32

5.       We have reviewed your response and revised disclosure in response to
our prior comment
         sixteen. It is our understanding that you did not account for your
collaboration agreement
         with Microsoft under ASC 606. Please tell us how you accounted for the
agreement,
         including the specific accounting literature you relied upon when
making such
         determination. In your response, address your accounting for the
following:
           the exchange of Microsoft's machine learning software at "no charge"
for your data
             and immunomics, diagnostic and bioinformatics expertise at "no
charge"
           the certain licenses to intellectual property rights granted to you
by Microsoft
           your exclusivity obligation to Microsoft with respect to
collaborations and projects
             that are substantially similar; and
           your commitment to purchase a minimum of $12 million in Azure cloud
services from
             Microsoft over a 7 year period.

         Quantify the related amounts recorded in your financial statements for
each period
         presented.
 Chad Robins
Adaptive Biotechnologies Corporation
May 23, 2019
Page 3

       You may contact Andi Carpenter at 202-551-3645 or Sharon Blume at
202-551-3474 if
you have questions regarding comments on the financial statements and related
matters. Please
contact Julia Griffith at 202-551-3267 or Justin Dobbie at 202-551-3469 with
any other
questions.



FirstName LastNameChad Robins                             Sincerely,
Comapany NameAdaptive Biotechnologies Corporation
                                                          Division of
Corporation Finance
May 23, 2019 Page 3                                       Office of Healthcare
& Insurance
FirstName LastName