Cartesian Therapeutics, Inc. — Director's Dealing 2017

Jun 30, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: SELECTA BIOSCIENCES INC (SELB)
CIK: 0001453687
Period of Report: 2017-06-29

Reporting Person: Siewers David (Chief Financial Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-06-29	Common Stock	M	3846	$0.47	Acquired	3882	Direct
2017-06-29	Common Stock	M	5770	$0.63	Acquired	9652	Direct
2017-06-29	Common Stock	S	9616	$20.0002	Disposed	36	Direct
2017-06-29	Common Stock	S	36	$20.00	Disposed	0	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-06-29	Employee Stock Option (right to buy)	$0.47	M	3846	Disposed	2019-09-19	Common Stock (3846)	Direct
2017-06-29	Employee Stock Option (right to buy)	$0.63	M	5770	Disposed	2020-09-06	Common Stock (5770)	Direct

Footnotes

F1: The transactions reported for the 3,846 shares were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 21, 2016.

F2: The transactions reported for the 5,770 shares were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 21, 2016.

F3: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $20.00 to $20.01, inclusive. The reporting person undertakes to provide to Issuer, any security holder of Issuer, or the staff of the Securities and Exchange commission, upon request, full information regarding the number of shares sold at each separate price within the set forth herein.

F4: The 36 shares sold were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 14, 2016.

F5: All shares underlying this option are fully vested.