UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-A

FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES

PURSUANT TO SECTION 12(b) OR (g) OF THE

SECURITIES EXCHANGE ACT OF 1934

Selecta Biosciences, Inc.

(Exact name of registrant as specified in its charter)

Securities to be registered pursuant to Section 12(b) of the Act:

If this form relates to the registration of a class of securities pursuant to Section 12(b) of the Exchange Act and is effective pursuant to General Instruction A.(c) or (e), check the following box. x

If this form relates to the registration of a class of securities pursuant to Section 12(g) of the Exchange Act and is effective pursuant to General Instruction A.(d) or (e), check the following box. o

If this form relates to the registration of a class of securities concurrently with a Regulation A offering, check the following box. o

Securities Act registration statement or Regulation A offering statement file number to which this form relates: 333-211555

Securities to be registered pursuant to Section 12(g) of the Act: None.

Item 1.                          Description of Registrant’s Securities to be Registered.

The description of the Common Stock, par value $0.0001 per share, of Selecta Biosciences, Inc. (the “Registrant”) under the heading “Description of capital stock” in the prospectus included in the Registrant’s Registration Statement on Form S-1 (File No. 333-211555), as initially filed with the Securities and Exchange Commission on May 24, 2016, including exhibits, and as may be subsequently amended (the “Registration Statement”), is hereby incorporated by reference. Any form of prospectus that constitutes part of the Registration Statement and is subsequently filed by the Registrant pursuant to Rule 424(b) under the Securities Act of 1933, as amended, shall be deemed to be incorporated by reference herein.

Item 2.                          Exhibits.

Pursuant to the Instructions as to Exhibits for Form 8-A, no exhibits are required to be filed because no other securities of the Registrant are registered on The NASDAQ Stock Market LLC and the securities registered hereby are not being registered pursuant to Section 12(g) of the Securities Exchange Act of 1934, as amended.

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SIGNATURE

Pursuant to the requirements of Section 12 of the Securities Exchange Act of 1934, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized.

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