May 30, 2019

VIA EDGAR AND OVERNIGHT COURIER

Office of Healthcare & Insurance

Division of Corporation Finance

Securities and Exchange Commission

100 F Street, N.E.

Washington, D.C. 20549

Justin Dobbie, Legal Branch Chief

Andi Carpenter

Julie Griffith

Draft Registration Statement on Form S-1

Submitted May 8, 2019

CIK No. 0001478320

Ladies and Gentlemen:

This letter is submitted on behalf of Adaptive Biotechnologies Corporation (the “Company”) in response to comments of the staff (the “Staff”) of the U.S. Securities and Exchange Commission (the “Commission”) with respect to Amendment No. 1 to the Company’s Draft Registration Statement on Form S-1 confidentially submitted on May 8, 2019 (the “Draft Registration Statement”), as set forth in the Staff’s letter dated May 23, 2019 (the “Comment Letter”).

Set forth below are the Company’s responses to the Staff’s comments in the Comment Letter. For reference purposes, the text of the Staff’s comments are reproduced in bold below, followed by the Company’s response to the comment. The numbered paragraphs below correspond to the numbered comments in the Comment Letter.

Additionally, the Company is concurrently publicly filing its Registration Statement on Form S-1 (the “Registration Statement”), which reflects revisions in response to the Comment Letter and certain other updates. For the convenience of the Staff, we are also sending, by overnight courier, copies of this letter and copies of the Registration Statement, marked to show changes from the Draft Registration Statement.

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

Overview, page 3

Company Response: In response to the Staff’s comment, the Company has revised the referenced disclosure on pages 3, 4, 110 and 111 of the Registration Statement.

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

Company Response: In response to the Staff’s comment, the Company has revised the referenced disclosure on pages 94 and 97 of the Registration Statement.

Our Market, page 105

Company Response: In response to the Staff’s comment, the Company has revised the referenced disclosure on page 107 of the Registration Statement.

Exclusive Forum, page 176

Company Response: In response to the Staff’s comment, the Company has revised the referenced disclosure on pages 74 and 181 of the Registration Statement.

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Consolidated Financial Statements Notes to Financial Statements Microsoft Collaboration Agreement, page F-32

Quantify the related amounts recorded in your financial statements for each period presented.

Company Response: For the Staff’s convenience, the Company has summarized the collaboration agreement (the Collaboration Agreement”) with Microsoft Corporation (“Microsoft”), followed by a detailed discussion of the Company’s accounting analysis.

Summary and Current Status of the Microsoft Collaboration Agreement

The Collaboration Agreement between the Company and Microsoft is intended to enable the parties to work together toward creating:

To those ends, each party will contribute know-how to the development efforts, with neither party having economic obligations to the other for development costs or commercialization results. Contemporaneously, the Company also entered into an agreement with Microsoft to purchase a minimum of $12.0 million in Microsoft Azure cloud services over a seven-year period. The Company determined that the prices to be paid to Microsoft for these respective services were at market terms for similar arrangements.

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The algorithmic-based methods and computational models to be developed have not previously been developed for any applications within the field of diagnostics, therapeutics and immunological research (the “Field of Use”). The computational models and machine learning efforts may prove to be unsuccessful and may never be fully developed. There was no commercial precedent for the intended outputs of the collaboration, and the parties did not establish development milestones or revenue sharing arrangements in the Collaboration Agreement. Microsoft has not previously entered into other agreements similar to the Collaboration Agreement. The economic terms of use by the Company of any AI Immunomics Services were left to future separate negotiation.

Limited license rights to existing and future technology, as well as any intellectual property rights created, were granted in defined fields of use to enable the collaboration to proceed. Except for its ability to sell any Algorithms it develops (and potentially AI Immunomics Services should the database architecture/software it may develop be informed by content licensed from the Company), Microsoft’s license rights fall outside of the Field of Use. Otherwise, license rights within the Field of Use are reserved to the Company.

If any AI Immunomics Services are developed, the Company agrees to exclusively use them for hosting and providing access to the TCR-antigen map data to be generated. The Company has also agreed to shift all of its cloud-based applications to the Microsoft Azure cloud service for exclusive use over a seven-year period, at arms-length market prices; in this regard, the Company has entered into Mircosoft’s standard Azure cloud services agreement.

To date, the activities performed pursuant to the Collaboration Agreement have consisted of the parties engaging in development planning, including the establishment of meeting cadences and collaboration staffing, and building the infrastructure that will be needed for the collaboration to proceed, including a laboratory that the Company plans to open in the third quarter of 2019, which will be used to generate and port TCR-antigen map data to Microsoft. Data the Company has shared with Microsoft to date has been limited to demonstrations of potential training sets. Microsoft has not provided any Algorithms or AI Immunomics Services to the Company.

Analysis of the Company’s Accounting for the Collaboration Agreement

To account for the Collaboration Agreement, the Company first determined that the agreement met the criteria to be a collaboration arrangement as defined under ASC Topic 808, Collaboration Agreements (“ASC 808”), as both parties are active participants in the activity and are exposed to significant risks and rewards that are dependent on the commercial success of the activity. Both parties have granted each other exclusivity relating to any substantially similar collaborations. Since ASC 808 does not provide guidance on how to account for the activities under the collaboration, and the Company determined that Microsoft did not meet the definition of a customer under ASC Topic 606, Contracts with Customers, the Company referenced other generally accepted accounting principles to determine the appropriate recognition and measurement guidance to account for the activities to be performed and/or received under the Collaboration Agreement. The Company identified that there were two units of accounting under the arrangement as follows:

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(1) Assessment and accounting for the Microsoft Azure cloud services commitment

To account for the commitment to purchase a minimum of $12.0 million in Microsoft Azure cloud services over a seven-year period, the Company determined that the prices to be paid to Microsoft for these respective services were at market terms for similar arrangements. This determination was based on references to the Company’s existing cloud services arrangements with other third parties and its knowledge of respective pricing from other cloud service providers. As a result, the Company assessed the accounting of the Microsoft Azure cloud and related services commitment separate from the remaining aspects of the collaboration. At inception and at present, the Company expects to meet the minimum volume purchase commitment of $12.0 million and, therefore, does not expect to make any payments to Microsoft that would not involve the actual use of the cloud services in the ordinary course of business. The Company accounts for the services as the cloud services are provided to the Company, and it records expense in the statement of operations based on the underlying activities which are hosted on the cloud services. The Company did not receive any Microsoft Azure cloud services in 2017. In 2018, the Company recorded $0.5 million in research and development activities related to these services.

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(2) Assessment and accounting for the exchange of non-monetary assets between both parties

Since the remaining elements of the arrangement were highly interrelated to the overall objectives of the collaboration, the Company determined that the remaining elements of the Collaboration Agreement should be evaluated as one unit of account.

The Company applied the guidance under ASC Topic 845, Nonmonetary Transactions (“ASC 845”), by analogy as this is the most relevant interpretative accounting literature to the specific set of collaboration activities to be performed by the Company and Microsoft.

The Company acknowledges that ASC 845-10-25-1 excludes transactions where the transferor has substantial continuing involvement in the transferred asset. However, since ASC 845 contains specific literature to address the transfers of the respective nonmonetary assets between the parties in this agreement, and the intent of the agreement was for each party to retain commercial and economic rights to its own developed technologies as opposed to the development of jointly owned assets with economic rights to be shared by the parties, the Company believed this guidance to be appropriate.

Based on the evaluation of the facts and circumstances in application of ASC 845, the Company concluded that it should not record any income or expense except for the costs pertaining to the research and development activities performed by its employees and utilized in connection with the development of the TCR-antigen map in support of the collaboration. To make this determination the Company referenced ASC 845-10-30-3:

A nonmonetary exchange shall be measured based on the recorded amount (after reduction, if appropriate, for an indicated impairment of value as discussed in paragraph 360-10-40-4) of the nonmonetary asset(s) relinquished, and not on the fair values of the exchanged assets, if any of the following conditions apply:

Given the structure and intent of the arrangement was to provide protective rights for each party to develop its own respective assets by leveraging each other’s know-how, the Company believes that ASC 845-10-30-3(a) is applicable to each of the “no charge” services, the licenses to intellectual property rights and the exclusivity obligations to and from Microsoft. This is based on the following guidance under ASC 845-10-30-8:

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Fair value should be regarded as not determinable within reasonable limits if major uncertainties exist about the realizability of the value that would be assigned to an asset received in a nonmonetary transaction accounted for at fair value. An exchange involving parties with essentially opposing interests is not considered a prerequisite to determining a fair value of a nonmonetary asset transferred; nor does an exchange ensure that a fair value for accounting purposes can be ascertained within reasonable limits. If neither the fair value of a nonmonetary asset transferred nor the fair value of a nonmonetary asset received in exchange is determinable within reasonable limits, the recorded amount of the nonmonetary asset transferred from the entity may be the only available measure of the transaction.

(Emphasis added.) As part of the assessment of the Collaboration Agreement, the Company determined that major uncertainties exist about the realizability of the value that would be assigned to the respective assets received and the assets relinquished under the agreement. Specifically, the Company considered the following factors to make this determination:

Assets received by the Company:

Assets relinquished/provided to Microsoft:

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Given the substantive uncertainty at inception as it relates to a successful outcome of the collaboration, the royalty-free licenses granted, and the future negotiation necessary regarding the terms on which the Company would use any AI Immunomics Services developed by Microsoft, the Company does not believe there are reasonable inputs that could be developed to determine a reliable fair value for the collaboration at this point in time. Further, there are major uncertainties about the realizability of value for any asset received.

Given the above factors in applying ASC 845-10-30-8, the accounting for the collaboration should be based on the carrying amount of the assets given up. Since the Company does not have a recorded carrying amount for any of the assets given up under the Collaboration Agreement, it did not record any respective income or loss pertaining to the Collaboration Agreement in any of the periods presented in its financial statements.

The Company recognizes that the application of this practical exception under ASC 845 is a matter that requires significant judgment based on the facts and circumstances of the non-monetary exchanges. As a result, the Company evaluated other qualitative factors to assess, if a valuation were to be developed, if it would result in material value conveyed to either party under the collaboration. In addition to the factors identified above that limit the reliability of any inputs that would be necessary to create a reliable estimate of fair value, the following events subsequent to the inception of the arrangement were assessed:

Given the stage of development activities and the novel approaches being applied under the collaboration, and the Company’s retrospective evaluation of activities that were performed during the first year of the collaboration, the Company does not believe either at inception or currently any fair value measurement would result in the recognition of a material asset or an increase to the Company’s income and increase to expenses.

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The Company has also revised its disclosure in footnote 15 to its annual financial statements, which begins on page F-32 of the Registration Statement, to clarify its accounting for the Collaboration Agreement.

[Remainder of page intentionally blank. Signature page follows.]

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Should the Staff have additional questions or comments regarding this letter or the Registration Statement, please do not hesitate to contact the undersigned at (206) 839-4845 or andrew.ledbetter@dlapiper.com.

Enclosure