SYNLOGIC, INC. — Director's Dealing 2017

Aug 30, 2017

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: SYNLOGIC, INC. (SYBX)
CIK: 0001527599
Period of Report: 2017-08-28

Reporting Person: Leschly Nick (Director)

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	23150	Direct

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Stock Option (right to buy)	$13.53	2027-05-15	Common Stock (18967)		Direct

Footnotes

F1: Shares of capital stock of the corporation then known as Synlogic, Inc. ("Old Synlogic") were converted into shares of the Issuer pursuant to that certain Agreement and Plan of Merger and Reorganization, dated as of May 15, 2017, by and among the Issuer, Meerkat Merger Sub, Inc. and Old Synlogic (the "Merger Agreement"). Pursuant to the terms of the Merger Agreement, each share of capital stock was exchanged for 0.5532 shares of the Issuer's common stock, giving effect to a reverse split of the Issuer's common stock of 7-to-1.

F2: On May 15, 2017, Reporting Person was granted 41,849 shares of common stock of Old Synlogic subject to a restricted stock agreement, dated May 15, 2017, by and between Old Synlogic and the Reporting Person, under the 2017 Stock Plan (the "2017 Plan"). Pursuant to the Merger Agreement, this common stock was converted into 23,150 shares of the Issuer's common stock. One-fourth of the total number of shares subject to the restricted stock agreement vest on March 15, 2017 and the remainder vest in equal monthly installments until March 15, 2020, provided that at the relevant vesting dates the Reporting Person continues service to the Issuer as defined in and as determined under the 2017 Plan.

F3: On May 15, 2017, Reporting Person was granted an option to purchase 34,287 shares of common stock of Old Synlogic under the 2017 Plan at an exercise price of $7.48 per share. Pursuant to the Merger Agreement, this option was converted into an option to purchase 18,967 shares of the Issuer's common stock at a per share exercise price of $13.53. One fourth of the total number of shares subject to the option vest on March 15, 2017 and the remainder vest in equal monthly installments until March 15, 2020, provided that at the relevant vesting dates the Reporting Person continues service to the Issuer as defined in and as determined under the Plan. The option expires ten years after the date of the grant.