Ryan Fischesser - Oct 6, 2022 Form 4 Insider Report for Caribou Biosciences, Inc. (CRBU)

Role: VP of Finance and Controller
Signature: /s/ Barbara G. McClung, as attorney-in-fact
Stock symbol: CRBU
Transactions as of: Oct 6, 2022
Transactions value $: -$88,653
Form type: 4
Date filed: 10/7/2022, 05:13 PM
Previous filing: Aug 24, 2022

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	CRBU	Common Stock	Sale	-$108K	-10K	-8.31%	$10.80	110K	Oct 6, 2022	Direct	F1, F2
transaction	CRBU	Common Stock	Options Exercise	$7.64K	+2.84K	+2.57%	$2.69	113K	Oct 6, 2022	Direct	F2
transaction	CRBU	Common Stock	Options Exercise	$11.7K	+2.84K	+2.51%	$4.11	116K	Oct 6, 2022	Direct	F2

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	CRBU	Option to purchase Common Stock	Options Exercise	$0	-2.84K	-62.49%	$0.00	1.7K	Oct 6, 2022	Common Stock	2.84K	$2.69	Direct	F3
transaction	CRBU	Option to purchase Common Stock	Options Exercise	$0	-2.84K	-15.62%	$0.00	15.3K	Oct 6, 2022	Common Stock	2.84K	$4.11	Direct	F4

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $10.67 to $10.94, inclusive. The reporting person undertakes to provide to Caribou Biosciences, Inc., any security holder of Caribou Biosciences, Inc., 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 range set forth in footnote (1) to this Form 4.
F2	Includes 4,848 shares represented by restricted stock units ("RSUs") that vest in two equal annual installments beginning on August 22, 2023, subject to the reporting person's continued service to the Issuer through the applicable vesting dates.
F3	1/4th of the shares subject to this option vested on January 1, 2020 and an additional 1/48th of the aggregate number of shares subject to the option have vested or will vest on the corresponding day of each month thereafter until the option is fully vested on January 1, 2023, subject to the reporting person's continued service to the Issuer through the applicable vesting dates.
F4	1/4th of the shares subject to this option vested on January 1, 2022 and an additional 1/48th of the aggregate number of shares subject to the option have vested or will vest on the corresponding day of each month thereafter until the option is fully vested on January 1, 2025, subject to the reporting person's continued service to the Issuer through the applicable vesting dates.