|SERES THERAPEUTICS, INC. filed this Form DEFA14A on 04/30/2018|
*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to Be
Held on June 26, 2018 . SERES THERAPEUTICS, INC. Meeting Information Meeting Type: Annual Meeting For holders as of: April 27, 2018 Date: June 26, 2018 Time: 8:00 AM EDT Location: Seres Therapeutics, Inc. 200 Sidney Street Cambridge, MA 02139 B A R
C O D E SERES THERAPEUTICS, INC. 200 SIDNEY STREET CAMBRIDGE, MA 02139 Investor Address Line 1 Investor Address Line 2 Investor Address Line 3 Investor Address Line 4 Investor Address Line 5 John Sample 1234 ANYWHERE STREET ANY CITY, ON A1A 1A1 1 OF
2 12 15 0000379634_1 R22.214.171.124 You are receiving this communication because you hold shares in the above named company. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more
complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important
information contained in the proxy materials before voting. See the reverse side of this notice to obtain proxy materials and voting instructions. Broadridge Internal Use Only Job # Envelope # Sequence # # of # Sequence #
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