April 25, 2019

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

       Re: Adaptive Biotechnologies Corporation
           Draft Registration Statement on Form S-1
           Submitted March 29, 2019
           CIK No. 0001478320

Dear Mr. Robins:

       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

Prospectus Summary, page 1

1.     We note your disclosure that you are a commercial-stage company
advancing the field of
       immune driven medicine. It appears from the pipeline table on page 3
that you have two
       commercial-stage products approved by the FDA and multiple products in
earlier stages
       of development. Please revise your summary to clearly distinguish your
commercial-
       stage products from those in development. We note, for example, that
your reference to
       "services tailored to each individual patient" suggests that you have
already
       commercialized such services.
 Chad Robins
FirstName LastNameChadCorporation
Adaptive Biotechnologies Robins
Comapany NameAdaptive Biotechnologies Corporation
April 25, 2019
April 2 2019 Page 2
Page 25,
FirstName LastName
2.       Refer to your statement in paragraph three of the Overview that
immune-driven medicine
         is one of the largest global addressable markets in healthcare, with a
potential market
         opportunity of greater than $48 billion for your portfolio. Please
provide us with support
         for your statements regarding the size of the market and that it is
one of the largest global
         addressable markets in healthcare.
3.       Please clarify what you mean by "translational research questions."
4.       To the extent you have not identified specific product candidates for
your TCR-based cell
         therapies business, please tell us why you believe it is appropriate
and material to
         investors to include this early stage pursuit in your product pipeline
table on page 3.
         Please also tell us what you mean by your references to "1st Shared"
and "2nd Shared."
5.       Please balance your statement that your goal is to change the course
of medicine by
         understanding and translating the adaptive immune system into new
products by
         clarifying, consistent with your disclosure on page 57, that no
TCR-based cellular
         therapies have been approved by the FDA or other regulatory agency.
Implications of Being an Emerging Growth Company, page 7

6.       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.
Risk Factors, page 11

7.       Please revise your disclosure to reconcile the various inconsistencies
between the
         description of your choice of forum provision on page 174 and the
description of it in the
         risk factor on page 73 (e.g., clarify in which documents the provision
or provisions will be
         contained, clarify the scope and terms of the provision, and which
courts shall serve as the
         exclusive forum under which circumstances). Please also disclose
whether the provision
         applies to actions arising under the Securities Act or Exchange Act.
Please note that we
         may have additional comments upon review of your revised disclosure
and associated
         organizational documents.
8.       Please revise your risk factor disclosure to address more specifically
the dilutive impact
         on investors in this offering that the conversion of outstanding
convertible preferred,
         exercise of the outstanding warrants, and stock option exercises
related to the Sequenta
         acquisition would have, or tell us why you believe this is not a
material risk.
Use of Proceeds , page 78

9.       For each of the purposes for which you will use the proceeds, please
quantify the amount
         you intend to allocate. Please also disclose how far into the
development of your pipeline
         candidates and drug discovery initiatives you expect the proceeds to
last. Refer to Item
 Chad Robins
Adaptive Biotechnologies Corporation
April 25, 2019
Page 3
         504 of Regulation S-K.
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 92

10.      We note from your Current Products and Pipeline disclosure on page 3
that you are
         developing products and services in both clinical diagnostics and
discovery, including
         clonoSEQ, ImmonoSEQDx and TCR-Based Cell Therapies. Please revise to
quantify
         your research and development expenses by product candidate. If you do
not keep track
         of such costs by product candidate, disclose that fact and the costs
incurred by the types of
         costs classified as research and development.
Critical Accounting Policies and Estimates
General, page 96

11.      Given the significance of goodwill to your balance sheet, please
expand your disclosure to
         provide a robust and comprehensive discussion regarding your
impairment testing policy.
         This discussion should include a description of key assumptions used
and how the key
         assumptions are determined, a description of the uncertainties
associated with the key
         assumptions and any potential events and/or circumstances that could
have a negative
         effect on the key assumptions.
Share-Based Compensation, page 97

12.      Once you have an estimated offering price or range, please explain to
us how you
         determined the fair value of the common stock underlying your equity
issuances and the
         reasons for any differences between the recent valuations of your
common stock leading
         up to the IPO 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.
Segment Information, page F-16

13.    Please revise to clarify, if true, that your CODM reviews your financial
information at the
FirstName LastNameChad Robins resource allocation decisions based on
consolidated results.
       consolidated level and makes
Comapany NameAdaptive Biotechnologies Corporation or service or group of
similar products
14.    Please revise to disclose revenues for each product
       and services. Refer to ASC 280-10-50-40.
April 25, 2019 Page 3
FirstName LastName
 Chad Robins
FirstName LastNameChadCorporation
Adaptive Biotechnologies Robins
Comapany NameAdaptive Biotechnologies Corporation
April 25, 2019
April 4 2019 Page 4
Page 25,
FirstName LastName
Consolidated Financial Statements
Notes to Financial Statements
Revenue
Genentech Collaboration Agreement, page F-19

15.      Please revise to disaggregate the $1.8 billion of additional
milestones you may receive
         under this agreement by development, regulatory and commercial
milestones.
Microsoft Collaboration Agreement, page F-32

16.      We note your disclosure concerning the Microsoft Agreement you entered
into in
         December 2017 for the purpose of developing a universal diagnostic
based on a single
         blood test. Please provide us with a comprehensive analysis of your
accounting for this
         agreement under ASC 606, including but not limited to the following:

             The transaction price and how it was determined
             The specific performance obligations you identified and how you
considered if they
             are distinct
             How you allocated the transaction price to the performance
obligations and whether
             you identified any variable consideration any constraint
             How you are recognizing revenue for each performance obligation
             How you considered the "no charge" components of the agreement in
your
             accounting; and
             How much revenue you recognized during each period presented and
how that
             revenue was classified on your income statement.
General

17.      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 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 Julie Griffith at 202-551-3267 or Justin Dobbie at 202-551-3469 with
any other
questions.



                                                              Sincerely,

                                                              Division of
Corporation Finance
                                                              Office of
Healthcare & Insurance