As filed with the Securities and Exchange Commission on January 22, 2020.

Registration No. 333-235989

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Amendment No. 1

to

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ADAPTIVE BIOTECHNOLOGIES CORPORATION

(Exact name of registrant as specified in its charter)

1551 Eastlake Avenue East, Suite 200

Seattle, Washington 98102

(206) 659-0067

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Chad Robins

Chief Executive Officer

1551 Eastlake Avenue East, Suite 200

Seattle, Washington 98102

(206) 659-0067

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale to the public: As soon as practicable after this registration statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box:  ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering:  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b–2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

EXPLANATORY NOTE

This Amendment No. 1 (“Amendment”) to the Registration Statement on Form S-1 (File No. 333-235989) (“Registration Statement”) of Adaptive Biotechnologies Corporation is being filed solely for the purpose of filing Exhibit 1.1, as indicated in Item 16 of Part II of the Registration Statement. Accordingly, this Amendment consists only of the facing page, this explanatory note, Part II of the Registration Statement, the signature page to this Amendment and the filed exhibit. The preliminary prospectus is unchanged and has been omitted from this Amendment.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 13. Other Expenses of Issuance and Distribution

The following is a statement of the costs and expenses, other than the underwriting discounts and commissions, to be incurred by us in connection with the distribution of the securities registered under this registration statement. All amounts are estimated except the SEC registration fee and the FINRA filing fee.

Item 14. Indemnification of Directors and Officers

RCW 23B.08.320 permits a Washington corporation to, through its articles of incorporation, eliminate or limit the personal liability of a director to the corporation or its shareholders for monetary damages for conduct as a director, except for the following:

RCW 23B.08.510 authorizes a Washington corporation to indemnify an individual made a party to a proceeding because the individual is or was a director against liability incurred in the proceeding if:

Notwithstanding the forgoing, a Washington corporation may not indemnify a director under RCW 23B.08.510 in connection with (a) a proceeding by or on behalf of the corporation in which the director was adjudged liable to the corporation or (b) any other proceeding charging improper personal benefit to the director, in which the director was adjudged liable on the basis that personal benefit was improperly received by the director. Additionally, where a proceeding is by or on behalf of the corporation, the indemnification permitted under RCW 23B.08.510 is limited to reasonable expenses incurred in connection with the proceeding.

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RCW 23B.08.520 mandates a Washington corporation to indemnify a director who was wholly successful, on the merits or otherwise, in the defense of any proceeding to which the director was a party because of being a director of the corporation against reasonable expenses incurred by the director in connection with the proceeding, unless such indemnification is limited in the corporation’s articles of incorporation. Our Articles of Incorporation do not contain any such limitation.

RCW 23B.08.540 permits court-ordered indemnification, unless a corporation’s articles of incorporation provides otherwise. Pursuant to this provision, in the absence of a contrary provision in a corporation’s articles of incorporation, a director who is a party to a proceeding may apply for indemnification or advance of expenses to the court conducting the proceeding or to another court of competent jurisdiction, and such court may order indemnification or advance of expenses if it makes certain determinations.

Under RCW 23B.08.570, unless a corporation’s articles of incorporation provide otherwise, an officer of a Washington corporation who is not a director is also entitled to mandatory indemnification under RCW 23B.08.520 and court-ordered indemnification under RCW 23B.08.540, each of which sections are summarized above, to the same extent as a director. Further, a Washington corporation may indemnify an officer, employee or agent of the corporation under RCW 23B.08.510, to the same extent as a director.

RCW 23B.08.580 permits a corporation to purchase and maintain insurance on behalf of any individual who is or was a director, officer, employee or agent of the corporation, or who while a director, officer, employee or agent of the corporation, is or was serving at the corporation’s request as a director, officer, partner, trustee, employee or agent of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise, against liability asserted against or incurred by the individual in that capacity or arising from the individual’s status as a director, officer, employee or agent, whether or not the corporation would have power to indemnify such individual against the same liability under RCW 23B.08.510 and 23B.08.520.

Our Articles of Incorporation and our Bylaws provide that we will indemnify our directors and officers to the fullest extent permitted under Washington law.

We have entered into indemnification agreements with each of our current directors and executive officers, and may enter into indemnification agreements with future directors and executive officers, to provide such directors and officers, additional contractual assurances regarding the scope of the indemnification set forth in our Articles of Incorporation and our Bylaws and to provide additional procedural protections.

We may also purchase and maintain liability insurance on behalf of our directors, officers, employees, and agents. We currently maintain a liability insurance policy pursuant to which our directors and officers may be indemnified against liability incurred as a result of serving in their capacities as directors and officers, subject to certain exclusions.

The underwriting agreement is expected to provide for indemnification by the underwriters of us and our officers and directors, and by us of the underwriters, against certain liabilities, including liabilities arising under the Securities Act.

Item 15. Recent Sales of Unregistered Securities

The following sets forth information regarding all unregistered securities we have sold since January 17, 2017.

(a) Sales of Preferred Stock

On December 11, 2017 we entered into a Series F-1 Preferred Stock Purchase Agreement, pursuant to which we issued and sold an aggregate of 4,686,649 shares of our Series F-1 convertible preferred stock at a price per share of $10.6686, for an aggregate purchase price of $49,999,984.

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No underwriters were involved in the foregoing sales of securities. The sales of securities described above were deemed to be exempt from registration pursuant to Section 4(a)(2) of the Securities Act, including Regulation D and Rule 506 promulgated thereunder, as transactions by an issuer not involving a public offering. All of the purchasers in these transactions represented to us in connection with their purchase that they were acquiring the securities for investment and not distribution, that they could bear the risks of the investment and could hold the securities for an indefinite period of time. Such purchasers received written disclosures that the securities had not been registered under the Securities Act and that any resale must be made pursuant to a registration or an available exemption from such registration. All of the foregoing securities are deemed restricted securities for the purposes of the Securities Act.

(b) Grants and Exercises of Stock Options

In connection with our Sequenta Acquisition, we assumed stock options to purchase an aggregate of 1,574,045 shares of our Series E-1 convertible preferred stock with exercise prices ranging from $0.10 to $0.92 per share to employees, directors and consultants pursuant to our Sequenta Plan. During the period beginning January 17, 2017 and ending July 1, 2019, 555,234 shares of Series E-1 convertible preferred stock were issued upon the exercise of stock options pursuant to our Sequenta Plan, which were each converted into one share of our common stock in July 2019 upon the closing of our initial public offering.

During the period beginning January 17, 2017 and ending July 1, 2019, we granted stock options to purchase an aggregate of 10,259,452 shares of our common stock, with exercise prices ranging from $6.27 to $9.62 per share, to employees, directors and consultants pursuant to the 2009 Plan. During the period beginning January 17, 2017 and ending July 1, 2019, 1,570,940 shares of common stock were issued upon the exercise of stock options pursuant to the 2009 Plan.

The issuances of the securities described above were exempt from registration pursuant to Section 4(a)(2) of the Securities Act as transactions by an issuer not involving a public offering or Rule 701 promulgated under the Securities Act as transactions pursuant to compensatory benefit plans. The shares of common stock issued upon the exercise of options are deemed to be restricted securities for purposes of the Securities Act.

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Item 16. Exhibits and Financial Statement Schedules.

(a) Exhibits

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(b) Financial statement schedules. Schedules not listed above have been omitted because the information required to be set forth therein is not applicable or is shown either in the financial statements or the notes thereto.

Item 17. Undertakings

The undersigned registrant hereby undertakes that:

Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Seattle, State of Washington, on January 22, 2020.

Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed below by the following persons in the capacities and on the dates indicated.

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