Document



Security Type	Security Class Title	Fee Calculation Rule	Amount Registered(1)	Proposed Maximum Offering Price Per Share	Maximum Aggregate Offering Price	Fee Rate	Amount of Registration Fee
Equity	2021 Stock Option and Incentive Plan Common Stock, par value $0.0001 per share	Rule 457(c) and Rule 457(h)(1)	2,531,579 (2)	$4.36 (3)	$11,037,684.44	$0.0001476	$1,629.16
Equity	2021 Employee Stock Purchase Plan Common Stock, par value $0.0001 per share	Rule 457(c) and Rule 457(h)(1)	233,302 (4)	$3.71 (5)	$865,550.42	$0.0001476	$80.24
Total Offering Amounts					$11,903,234.86		$1,709.40
Total Fee Offsets							-
Net Fee Due							$1,709.40


(1)			Pursuant to Rule 416 under the Securities Act of 1933, as amended (the “Securities Act”), this Registration Statement shall also cover any additional shares of common stock, par value $0.0001 per share (the “common stock”), of 2seventy bio, Inc. (the “Registrant”) which become issuable under the 2seventy bio, Inc. 2021 Stock Option and Incentive Plan (the “2021 Plan”) or the 2seventy bio, Inc. 2021 Employee Stock Purchase Plan (the “2021 ESPP”) by reason of any stock dividend, stock split, recapitalization or any other similar transaction effected without the receipt of consideration which results in an increase in the number of our outstanding shares of common stock. Pursuant to Rule 416(c) under the Securities Act, this Registration Statement shall also cover an indeterminate amount of interests to be offered or sold pursuant to the employee benefit plans described herein.
(2)			Represents an automatic increase of 2,531,579 shares of common stock to the number of shares available for issuance under the 2021 Plan effective as of January 1, 2024. Shares available for issuance under the 2021 Plan were previously registered on Form S-8 filed with the Securities and Exchange Commission on November 1, 2021 (File No. 333-260669), March 25, 2022 (File No.: 333-263853 and March 17, 2023 (File No.: 333-270660).
(3)			Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) and (h)(1) of the Securities Act, and based on $4.36, the average of the high and low sale prices of the Registrant’s common stock as reported on the Nasdaq Global Market on December 29, 2023.
(4)			Represents an automatic increase of 233,302 shares of common stock to the number of shares available for issuance under the 2021 ESPP effective as of January 1, 2024. Shares available for issuance under the 2021 ESPP were previously registered on Form S-8 filed with the Securities and Exchange Commission on November 1, 2021 (File No. 333-260669), March 25, 2022 (File No.: 333-263853 and March 17, 2023 (File No.: 333-270660).
(5)			Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(c) and (h)(1) of the Securities Act, and based on 85% of $4.36, the average of the high and low sale prices of the Registrant’s common stock as reported on the Nasdaq Global Market on December 29, 2023. Pursuant to the 2021 ESPP, the purchase price of the shares of common stock reserved for issuance thereunder will be at a maximum discount of 15% of the fair market value of a share of common stock on the first trading day of the applicable offering period or on the last trading day of the applicable offering period, whichever is less.