Caribou Biosciences, Inc. — Director's Dealing 2021

Jul 29, 2021

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Caribou Biosciences, Inc. (CRBU)
CIK: 0001619856
Period of Report: 2021-07-27

Reporting Person: FMR LLC (See Remark 1)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2021-07-27	Common Stock	C	770510	—	Acquired	770510	Indirect
2021-07-27	Common Stock	C	1070427	—	Acquired	1840937	Indirect
2021-07-27	Common Stock	C	17572	—	Acquired	17572	Indirect
2021-07-27	Common Stock	C	1464775	—	Acquired	1464775	Indirect

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2021-07-27	Series B Preferred Stock	$	C	423823	Disposed		Common Stock (770510)	Indirect
2021-07-27	Series A-1 Preferred Stock	$	C	588794	Disposed		Common Stock (1070427)	Indirect
2021-07-27	Series A-1 Preferred Stock	$	C	9666	Disposed		Common Stock (17572)	Indirect
2021-07-27	Series A-1 Preferred Stock	$	C	805707	Disposed		Common Stock (1464775)	Indirect

Footnotes

F1: On July 27, 2021 , in connection with the completion of the issuer's initial public offering, each share of Series A-1 and Series B Preferred Stock converted into 1.818 share of Common Stock.